Can anyone confidently identify this noise? A833 4 speed

1968 Plymouth GTX, mild early 70's 440, 11" CenterForce DualFriction, new input bushing, 23 spline of unknown sourcing (looks to never have been apart, shifts great though). 3.55 SG fresh, original driveshaft.
There is a noise that sounds much like an old school buzzer that eminates at speeds above 50mph and remains constant above that; it goes away consistently below that speed and finally does go away at 70+ mph.
Everything in the clutch/flywheel is new and Brewer's sourced.
Tailshaft bushing and seal are also new. Speedo gear is new as well; I had it out to inspect and it's flawless and I've eliminated the cable as a possibility as well.

The noise is not engine speed dependent; only vehicle speed makes it happen, whether clutch in/out, regardless of gear (or in neutral). Revving the engine in neutral, no difference.
It comes on all at once, like a light switch being flicked.

I have a video on YouTube of it occurring in real time:
A833 Noise - Speedometer Disconnected at Transmission

Can anyone confidently recognize this noise?
TIA!!

I figured it out you are driving a Superbee not a GTX by the sounds of that Buzzing noise.

Somebody surely recognizes that sound??

Sounds kind of like some sort of bushing, or bearing. Does the engine have a cast crank, and if so, does it have the proper flywheel, and balancer? I'm in Morristown, maybe we can get together and figure it out.

I hear it, sure don't know what it is. But first thing I would do is grab shifter handle, try moving a hair each way to try to change noise. gives ya a better idea where to look. Be very weird if it ends up as a relay buzzing somewhere.

That sounds like a speedometer cable binding at/near the transmission to me. That is exactly what my dremel tool extension cable sounds like when I get it in too tight of a loop/radius. I would disconnect the speedo cable and see if it goes away. If the cable is clipped to the floorboard to keep it in place it would make a perfect sounding board for it.

Hey, that's very gracious of you. I'd kill for access to a lift right now. :-)
Darn good question on the engine and I don't know for sure, but when I got the engine in shipping, I took pictures and posted on the FBBO forum and asked others' opinions. The consensus was that it was forged and since it came with those types of balancers and flywheels, I called it good.
If the problem was a gradual harmonic vibration that became stronger (or lesser) with speed, I'd certainly be looking at that possibility, though, sure - but it isn't, as you can hear.
This comes on all at once with a certain speed.

Oh trust me, the shifter got wrangled every which way, including "more in gear", out of gear, every position short of reverse while going down the highway. Nada.
Sounds like an old seat belt buzzer, eh? :-)
It isn't. There's nothing in that area electrical, short of the reverse light switch of course.

Thanks (and I agreed with you initially because that's what it sounds like), but as I posted, the speedo gear and cable are no longer suspects. In fact, the speedo cable is disconnected at the transmission at the time I made the video in the hopes that would have cured it.
Sadly, it didn't.

Thanks for all the guesses so far. I appreciate the help!
Man, I'm hoping someone hears it and says "well sure, dumbass, it's this!" :-)

Does it do it when in 2nd? Could be the shift fork rattling?

I tried every shifter position short of reverse.
Thanks!

It does sound like a dry bushing but you have covered all the usual suspects. The only thing I can think of would be trying a differn't speedo adapter then see if someone can loan you a differn't drive shaft. You cant feel it through the shifter? Does it stop when you kick it into neutral?

Gus

I gotta figure if the speedo pinion is in perfect shape (it is) and the speedometer itself works flawlessly, then I got the "lash" set correctly on the adapter. I suppose I could just pull out the pinion and plug off the hole in the adapter, then give that a shot?
I'm gonna do it. What would it hurt to try? Thanks!

No sir on the neutral. Again, shifter position and clutch position do not affect the noise at all. Any gear or neutral, doesn't matter.
Thanks!

Can anyone confidently recognize this noise?
TIA!! [/quote]

Sounds to me like rear main bearing in the transmission??????

Okay, if I've got this right.

1) Noise is dependent on road speed, not engine speed.
2) Noise is present in neutral with enough road speed.
3) Noise is present with clutch depressed and enough road speed.

If the noise is present in neutral with the clutch depressed and enough road speed, the only thing that is rotating is the output shaft. I think the rear main bearing is a good guess.

1) as long as the rear tires are rotating, the rear main bearing is rotating.
2) As long as the rear tires are rotating, the rear main bearing is rotating
3) as long as the rear tires are rotating, the rear main bearing is rotating. When clutch is depressed, the input shaft stops rotating, hense, the front bearing stops rotating.

What are you mean when you say the lash is correct on the pinion adaptor?

It could also be the rear bushing in the tailshaft, where the slip yoke rides... Pull out the slip yoke and see what the machined surface looks like.

There are three different settings for the speedo adapter depending what tooth the speedo gear is. I think that is what he was referring to .

Easy/cheap stuff first:

I'd take a close look at the rear transmission mount.

Next would be a u-joint, but I can't say I've ever heard one make that kind of noise. Won't hurt to re-check them.

Great video: that helps alot.

Could it be the steel starter shield buzzing if equipped.

It sounds just like someone or something blowing on a piece of paper or thin plastic making a whistle like noise like we use to do when I was a kid, a long time ago

That's what I was wondering, cause the manual doesn't say anything about lash.

Yes, along with anything beyond or driven by the tail shaft, such as the speedo pinion and such.
The bearing is certainly a suspect, even though the noise doesn't sound like a bearing.

Referring to the speedometer pinion adapter there.
the lash is darn close because the speedo works perfectly and there is zero discernable wear on the speedometer pinion.

That bushing (and the seal) were replaced last fall with Brewers stuff. Oil hole was even clocked correctly on it.

Yessir! :-)

Thanks. As far as the mount goes, it's also brand new from Brewer's, as is the crossmember. Since the transmission is an early 70's dual shifter mount type, I had to get one of Dan Brewer's crossmembers that has the late 60's bolt holes but the early 70's mount. Kind of a hybrid.
Worked beautifully.
Yep on the u-joints. I reckon I'll replace those just because I don't know how old they are now, even though as you say it doesn't sound like one. No real discernable slop in them, though.
I'll replace the slip yoke too just because.

Well, that's the other end of the spectrum (and other end of the transmission, of course) but I can't say definitely not, either.
Stranger things have happened.
I think the key to this mystery is what I was doing to the car when this occurred.
I pulled away easy from a stop sign, then tromped on it once underway. A fast grab of 2nd, dropped the clutch pretty hard and laid down two black strips, then heard the noise as I eased back off the throttle.
It's been there ever since, even though the car drives just fine.
I get it up over 50 and the "switch" gets flipped and the racket begins, every time.

How would you feel about putting the car on jack stands and trying to pin point the noise while in gear? I mean the rear end on the stands and running it up till it does it? Maybe putting phone on a stick on record, and move it around till you found where it was coming from.

Ah yes. the reed effect. We used blades of grass to do that. :-)

I'm glad you asked that. :-)
We did just that last weekend. Put the rear end up on 4 jackstands, then cautiously ran it up through the gears. I was "driving" (and praying not to go flying through the wall into the house) while a friend was outside, down on the floor watching and listening.
I ran the car all the way up to an indicated 70mph. Could not get it to make the noise.
It occurred to me later that the noise starts after the car has been driven about 5 miles, so I guess something has to get warmed up before it will make the noise - and we didn't do that while the car was on jackstands.
Oy.

Warm it up for 6 miles. Then 'drive' it on the jack stands.

Use a LONG steel rod to listen to different parts/areas of the trans to narrow down the spot. A long rod like a dowel or even a floor jack handle. Hold it to your ear like an automotive stethoscope.

Maybe a bearing is coming apart.

Possible Pilot bearing?

I would imagine if it was that, it would change in pitch with engine speed?
Thanks!

Could very well be the rear main bearing, although it doesn't sound like a bearing at least to me.
I might deploy your steel rod method of detection, but I think I'd rather take the shifter boot off and "probe" through that hole with a smaller rod.
The thought of anyone getting under the car with anything while it is in gear and hauling just doesn't sit well with me.

I've just picked up a Moroso transmission "plug" (pipe stub with plastic cap on the end) that I'm told will fit in the output seal in lieu of the slip yoke. I might try to see if I can dry run the thing in the garage with that.
Perhaps eliminating the driveshaft/yoke from the process might prove illuminating?

I would think he has a pilot bushing, not a bearing
OP, is it a bearing or bushing?

Could very well be the rear main bearing, although it doesn't sound like a bearing at least to me.
[/quote] No way a main bearing failing lives that long, trust me on that

No way a main bearing failing lives that long, trust me on that [/quote]


Oh I don't know about that short life of a noisy bearing. I had one making bad noise for a couple years. Drove across the state a couple times towing my brother's cars on my trailer. Sounded like the rr, looked ok, but replaced it anyway. My brother thought it was the lr, it looked fine, but replaced it also. I finaly took apart the rearend and found the pinion bearing real bad.

Me thinks a ball bearing or tapered roller bearing with lubricant will live lot longer making noise than a engine MAIN bearing will

Ok, just for the heck of it

are you people saying 'main bearing' talking about the ENGINE'S rear main bearing? or the transmissions rear or front 'main' bearings?

The ENGINE has already been eliminated from making the noise, so that's OUT

stick with the TRANSMISSION'S bearings, thankyou.


None of my replies have anything to do with the engine, only the transmission bearings. After all, this discussion is about his TRANSMISSION, thankyou.

So lets all get on the same page: his TRANSMISSION, not his engine.

As I stated in my original post:
"...new input bushing..."

What I'm thinking too, although the thought of the rear main partially galling is tempting.
Still, I don't hear a bearing. I could be dead wrong, but I don't.

I reckon not. Exhaust, in this case 3" diameter, is dead in the way of doing much transmission prodding without at least plunking yourself down on the concrete to get an angle.

I don't see anyone talking about the engine. From what I've seen, the furthest forward I've seen mentioned is the input bushing so far.

Yes, for the record, I've pretty much ruled out anything to do with the engine (or the clutch, for that matter) because the noise does not change in frequency or speed itself. Further, it is not affected by RPM of the engine or whether the clutch is in or out. Doesn't care where the gear shift is either.
Thanks!

I count 2 people mention the ENGINE MAIN bearing. And a couple more, plus me, mention the TRANSMISSION MAIN/MAIN SHAFT BEARINGS BEARING/S.

I'd sure like to know what it is. I've never heard that noise before.

You can also remove the speedo pinion gear/adaptor and make a metal plate to cover the hole. They actualy make those plates. Then drive the car and see if the noise is still there. At the very least it would eliminate that possibility of the speedo cable gear assembly making the noise.

Maybe it's not in the trans, maybe it's on the underside of the floorboards?


Maybe it's something in or on the exhaust pipes.

Whenever I hear a "buzzing" type noise its some type of vibration or harmonics. It occurs at a certain speed that could be caused by tire noise or tire balance, or exhaust drone and something is vibrating. Heat shield that is loose or vibrating under certain conditions such as speed or rpm.
To me, its some type of vibration.

Sorry, hadn't gotten that far in the comments.
Speaking of not knowing what the noise is, none other than Dan Brewer has conversed with me a couple times this week and he's stumped, too!
I'm about ready to yank the trans and discard it at this point.

Yeah, I've written about doing that. Gets tiresome and messy, though - you lose fluid when you pull the speedo gear, then have to pump it back in the dang thing every time.
Nonetheless, that's what I'm doing next, followed by a replacement of the slip yoke and u-joints.
I figure those would need attention eventually anyways, so it's not a wasted effort to do so even if I wind up replacing the transmission. Worth a shot.

Doubtful, but can't say definitively not at this point.

Reviewing - these are KNOWN so far:
1. Speed is the only cause factor.
2. Noise comes on all at once, instantly - doesn't change in intensity or pitch once it starts.
3. Doesn't change with engine speed, clutch or shifter position.
4. Not speedometer cable.
5. Begins after the car has travelled a half dozen miles or so.
6. Begins at speed above 50mph.
7. Emanates from portion of transmission directly below/behind shifter.

Okay, let me throw this out. It started with a hard romp. Any chance that the vent baffle in the extension housing came loose and is 'fluttering'?

I agree with tman, that sounds like a vibration buzzing. Get under the car and check all the bolts holding your shifter in place, even the ones holding the aluminum mounting plate to the trans. It could also be the shift rods vibrating. Tape some rags, temporarily, to the shift rods and see if the noise changes. Make sure the shift rod links at the transmission are tight.

How about this. Remove the boot and such from the shifter, and while driving have someone stick their ear, or a probe to see if they can pin point the noise.
Were you at any of the Rogersville downtown cruise in's that they had on Friday night last summer? I had the 71 Road Runner, maybe we talked.

Probably next on the agenda, yep.
Thanks!

Yessir, we sure did talk. I gushed all over that black beauty. :-)

Dude, how far down this rat hole are you going to dig yourself into?
Transmission MAIN Bearing, which school did you learn that term from
Front input shaft bearing, rear output shaft bearing, cluster shaft needle bearings and some bushing in a lot of different stick shift transmissions, no automotive standard transmission I have ever heard of or read about mentions a transmission MAIN bearing in them
Do we really need to go on about your concerns on words used in this discussion

Sounds to me like rear main bearing in the transmission?????? [/quote]So, Cab_Burge, why don't you get on THIS person's case? HE was the first to call it 'main bearing'. lol I was just following along...so don't sweat it.

I don't sweat the petty stuff, ever

I'm just guessing like everyone else.

It's like a puzzle, enough people guess, someone will get it done/guess it.

I did a 4speed conversion on a 71 roadrunner years ago and had a very similar "buzzing" noise. turned out to be a bent drive shaft.

Shane

Its not good when your driveshaft turns into a guitar string

here are some thoughts, I would double over all nuts and bolts in the general area, could possibly be trans mount cross member bolts.
I would definitely run it with the axle tubes on jackstands and wheel chocks in the front and back of the front tires, WITH THE CAR POINTING OUT OF THE GARAGE with nothing in front of it, to see if noise is there with no road vibration.
When the noise is present You might want to step on the clutch and turn the ignition off to see if noise is still there with engine off.
If you decide to take the speedo gear out you could probably jack the back of the car as high as you can get it to minimize loss of oil.
While in there you should be able to see / poke at the vent baffle tin that is in there to see if its loose.

We've done the jackstands under the rear axle bit already; I "drove" the car that way while a friend bravely got down and watched from the side, but the car didn't make the noise on those stands.
He reported that the driveshaft looked remarkably smooth as I wound up buzzing the car all the way up to 70mph.
Made me nervous, I can tell you, even though we used 4 jackstands under the axle.
It only occurred to me later afterwards that the noise only starts after the car has been driven over 5 miles or so, so I reckon things have to warm up somewhat before the racket appears.

I've also already done the speedo pinion removal rhing; it looked perfect when I took it out (and yes, considerable fluid is drained when you do this that has to be returned). Further, the speedometer itself is one of the smoothest operating ones I've ever seen in an old car; GPS confirms I've got the right speedo pinion, too.
I tried speedo pinion in, out, cable on, cable off.
Nope.

When weather permits, I'm going to get a local shops' owner to go for a ride with me so he can hear it. He specializes in Mopars and has restored several.
If he can't come up with anything, I reckon I'll be left with little recourse but to swap out the transmission. :-(

Drive it 5 plus miles, then put it on the jack stands while warm and try it.

I have no update on this, sadly.
Weather went to crap and so did work demands, not to mention I wound up spending considerable time working on both the late-model hemi critters around here ('04 Ram and '12 Charger R/T).
Nothing other that what wound up being routine stuff, but have you ever changed the plugs in a hemi Ram? I've done it to this one since new, but this was the last time I'll ever do it - my rearranged and scarred innards won't take it anymore.
Cancer is a [censored], especially 3 times.
Someone else can do it next time.

Plan now is when the weather gets dry and warm enough to allow it, I'm going to take it by a local fellow who owns a repair shop to have a listen. He's a Mopar guy and has restored some in the past.
We'll see what he thinks in person.

Who you taking it to, if I may ask?

Chris Britton, but I'm not concrete on him touching the car. Did you have a suggestion?

Two guys actually, Kenny Drinnon here in town, he does mechanical stuff that I can't, and Bob Mayers in Greenville, he owner Performance Auto, he does excellent engine work, and does stuff like this at home on the weekends.

I appreciate the advice.
Mechanically, I can do pretty much anything so I don't typically let others work on my vehicles (short of factory recalls, of course).
Engine-wise, I'm pretty good to go right now.
I guess I'm saying I can fix whatever this is - but I need to figure out just exactly what it is.
Thanks!

Well, an update of sorts...

Weather has been downright New England-ish the last couple weeks and we have still more to come apparently. Anyways, I seized on a few hour window of opportunity today and ran the car over to the shop.
Fellow took a ride with me, heard the noise clear as day - and looked at me and said "I've never heard that before in my life".
I thought --------
He went through all I had done and came up with the conclusion that, based on what he was feeling/hearing in person, it could only be a bearing.
Reckon I concur at this point - the noise is getting worse with more driving and the gear lube I drained the other day to remove the speedo pinion didn't look so great, adding credence to the bearing theory.

Thought process quickly moved from there, past trying to fix this one (which would no doubt turn into a full blown rebuild quickly) to ok, guess I'll have to fetch another transmission - and if I go there, it won't be just any transmission.
It best come from a known good source and either have a warranty (hello, Passon or Brewer's) - or come from someone I seriously trust to get it from.
Only going to do this once. Really don't have the patience - or yes, time - to fool around with this for long.

Oh, and the real shocker of the day - he doesn't want to do the swap, either. He tells me this as I make note of the '71 'Cuda on one lift and the full tube frame 'Cuda in another bay.
He says he only works on his own Mopars now, not anyone else's - and "modern" stuff for customers. Says something else could go wrong during the job and he doesn't want that grief.
Whatever...
I got a couple other places in town that didn't bat an eye telling me they're not afraid of the job and they shouldn't be.
The one literally within a mile of my place says "yeah, bring it by or I can come give it a nice ride on the rollback. $100."
As in he wants $100 to do the job. Even expects me to be there when he does to "keep him straight".
I think I have a new buddy. :-)

Ok....Brewer's or Passon?
I'd love to do an 18 spline, but my brand new clutch setup is for a 23 spline 11".

I learned to rebuild NP833 from a factory service manuals years ago when I drag raced a 1970 Baracuda with a Hemi and 4 speed in NHRA stock, you can to
The hardest part is changing the 4 sets of needle bearings in the cluster gear, all the other regular bearings, both of them, are pressed on and off
I use to remove the rear bearing snap ring and then use the 1st and 2nd gear weight to push that bearing off by dropping the rear of the output shaft onto a 4x4 block of wood, worked good, never hurt a part
I would drive it back on with a steel sleeve or another used inner race and a brass drift and hammer
I ended up buying a Snap On bearing remover collar to remove the front bearings off of the input shaft with a home made press, it works good on the rear axle bearings also
BTW, I'm not sure that noise is a bearing noise, truthfully

I'm typically the same way, but not with transmissions. I've had them apart just to see how, but the interest ended right there. :-)
I don't have the patience (or the luxury of time) to rebuild this one, especially since it was a freebie to begin with and nothing special.

I'm not sure the noise is, well, anything specifically - I've just arrived at that conclusion by eliminating what it couldn't be - and since nobody has come up with anything else better, it'll get yanked and replaced, to be sorted out by someone else later maybe.

Question stands - who does the better rebuild, Brewer's or Passon?

Check out this thread, But if time is an issue and you're not ready to learn yet, I would send it to Brewers. They have a really nice packing crate(preformed foam & box that holds the Trans perfectly) to ship it back to you, maybe they could send you an empty crate/box so you can ship it to them the same way.

https://board.moparts.org/ubbthreads/ubbthreads.php/topics/2455719/1.html


also these are in the above but here's easier access.

pliers
https://www.ebay.com/itm/141762732578

info
http://www.forabodiesonly.com/mopar/ams/how-to-a-833-4-speed-rebuild-pics.85/
info
http://www.hotrod.com/articles/mopp-0403-rebuilding-the-a-833-four-speed-tranny/

I appreciate all the help, my friend, but...
Decision made, order placed.
Came down to a factor of time.
Brewer's is months behind in orders and won't have a unit available until the end of May (!).
Dan was honest in telling me that and I appreciate it.

Had a nice chat with Jamie at Passon just a bit ago. We spoke on several topics and he shed some light on things I had been wondering about in Mopar world in general.
Dude sounds tired but that's a good thing. He also sounds honest.
Three weeks on his time frame.
I placed an order with him on the spot, including a roller type input bearing to install in place of the bushing.
Wife is fussing. She'll get over it.

He recommended going back with the late 60's 23 spline unit since I still have that crossmember, even though he advised that the early 70's B/E unit I have now is no different mechanically, just on shifter mounting options and I have the modified crossmember for that as well, which I'll probably be selling.

Now the wait begins....

I wouldn't hesitate to get one form either of them. If you want to go 18 spline you just need another disc.

But be warned a rebuilt isn't going to be cheap .

Did he ask what size hole is in the bell housing for the bearing retainer?

Thanks. Yes, my having a new 23 spline clutch setup (an expensive one at that) is why another 23 spline transmission was ordered....and yes, they aren't cheap.
Nonetheless, it's already bought.

Since the transmission will be a late 60's 440 23 spline, that question is sort of already been answered.
11" bellhousing 2892262:
http://www.brewersperformance.com/proddetail.php?prod=BH262
Uses the 4.805 retainer.

Funny side story, though - the previous owner (who did the "conversion" on the car to a 4 speed) had installed a transmission with the smaller input retainer on this same bellhousing - so basically, the only thing centering the input shaft were the transmissions' 4 mounting bolts.
True story, looked funny once I took that one out. :-)

I hope your transmission is as good as the one I bought from him. It is perfect. You are right, he sounds a little sleepy on the phone but is willing to listen and answer any questions.

Thanks, me too. :-)

Makes me nervous to buy something of this size ($$$) over the phone without so much as an email confirmation, I can say.
Tried to contact him through his website, but that site isn't the best and that feature doesn't work, either.

I think Jammie has a day job, that's why it's hard to reach him. I bought my 4 speed over drive from him over the phone. Save the crate that it comes in.

I'ts crazy how far behind Brewer's is... I always go to them for my 4-speed stuff, but hard to do when they don't have it for a while.
I've talked to Jamie Passon twice, and both times he seemed like in his arrogance he didn't have time to sell me anything. May be his demeanor or personality, Idk. If he's bothered by me, I'll gladly spend the money with Wayne and Dan. Would love one of those 5 speeds, though.
Hopefully the new transmission solves the problem.

I would have bought from Dan in a heartbeat (and have many times before), but the delay in doing so just didn't sit well with me.
Having said that, it is making me nervous that Jamie hasn't returned either email or PM on facebook so far.

I've been dealing with Jamie for years now, and I have nothing but the highest praise for him. But he's been somewhat beaten into the ground with the development of this new transmission, it was orders of magnitude more involved than he ever dreamed it could be. He took on a gargantuan task for basically a one man shop.

All I can say it don't worry. He will take care of you, or he'll let you know he can't. I can also say from experience that just calling is the best way to get him, that has always worked best for me.

I heard from him today, makes me feel a ton better.
Told him I had just enough time to do this one last time and I chose to get one from the best in the biz. He liked that. :-)
Hey, I call 'em like I see 'em.

Either shop is a fine choice. Have dealt with both.

Transmission was received today in fine shape.

Let us know about that dang noise, I want to know what it is and what caused it

The Passon transmission was installed at the mechanics' shop this morning, myself assisting with the install.
Everything went back together fine but all hell broke loose on the test drive, which went all of 100 yards before an awful noise akin to what a starter sounds like on a small block Chevy when it needs LOTS of shimming.
In 1st or 2nd, it could be stopped by pushing back in the clutch; in 3rd it made it regardless of whether the clutch was in or out.

Got Passon on the phone and he requested to hear the noise, which I reproduced for him "live" while on the lift again.
The mechanic, who is knowledgeable on manual transmissions and has rebuilt many in his time, was under the car and pinpointed the issue to the 3-4 part of the transmission. Manual operation of the 3-4 shifter selector on the side of the transmission revealed pretty crappy, hard to operate.

I received what can honestly be described as a negative attitude over the phone, which was very disappointing. I'm into this transmission a good chunk of money; I don't need poor attitude and service, which is what occurred.
He's supposed to be sending me another one.
We'll see, but a wholly disappointing day, capped off by negative attitude over the phone. This isn't going well so far.

Is this a different noise from the original post or similar?Was the release/throwout bearing changed? What kind of clutch is in the car?

Very much different and emanating from a different portion of the transmission.
The clutch and throwout are both CenterForce units, both practically new (100 miles maybe).
It was scrutinized when I got the car back on the lift, making sure all was well there. All clutch linkage is new and from Brewer's.

Confirmed over center spring is out from under dash?

Oh trust me, it is. I did that and let me tell you...that's a load of fun, right there.

Today's update is a good one:
Jamie has agreed to take the transmission back and to refund me all charges. This news made me very happy; I'm glad to see him do the honorable thing here. We had a decent conversation via text and all has been arranged.
My old transmission is now in the hands of the mechanic and his friend the "expert". Once they've got it squared away, we'll tow the GTX back to him and the Passon unit will be removed and placed back in the crate for return; my old one will be re-installed in the car then, hopefully for good.
Fingers crossed...
Thanks to Jamie for stepping up here. Restores my faith a little bit. :-)

Good choice. It's always an advantage to be able to see your equipment come apart in front of you. Additionally, you are going to find what the original problems was. All good.

When your ORIGINAL trans is apart. Check the runout of the mainshaft to comfirm its not tweeked (bent).

Did you give Jamie the opportunity to sell you a rebuild kit?

Make sure you get the correct front 308 bearing if needed.

Jeff

I don't know squat about transmissions. I am trusting the trans guy to check it out and let me know what it needs. I did tell him the unit shifts and drives beautifully right now and to focus on finding out the source of the mystery noise/whirring/vibration at speeds above 50mph.

I don't know if it even needs rebuilding; I can tell you all the forward gears and synchros feel great. No popping out of gear, no grinding, etc. She shifts as nicely without the clutch as she does with it, pretty much.

In other news, I had a nice conversation with Dan Brewer this morning. I called with a question and he's always, without fail, gone out of his way to help me and answer questions in the past.
Today was no exception. Real nice guy.
We chatted about his current backlog for rebuilt transmissions (2 months now if anyone is wondering) and that he doesn't trust anyone else to do them except him - and that's not going to change.
He did express some sympathy for his direct competitor, saying it was a hard gig to try to do everything himself, but that was how it was going to be as long as he did it.

I asked today about the slip yoke and whether it was possible my original problem could involve that. He doubted it (and he did remember watching my video of the noise in question) and asked if anything had been resolved about it so he could put it in his own memory bank in the future.
Nope, nothing yet Dan. Working on it. :-)

I have a question: When you disconnected the speedo did you only disconnect at dash??? I'm asking because then the cable would still be turning and cables sometimes make weird sounds...
Ron

It would be much easier to disconnect at the transmission, eh?
Yep. Yep, it was.
The goal was to eliminate the cable as a possible source of the noise, after all. Only one way to do that.

The speedometer gear was also removed at one point to eliminate it as well. Nada.

OK!!

The word from the transmission shop today is that my old unit (the one with the mystery noise, remember?) is only in need of two (2) main bearings (I guess that would be "both" main bearings, right?) and a front seal.
That's it.
As I guessed, all the gears and synchros were in real nice shape, lending to why the unit drove so nicely.

Those who guessed "rear main bearing" or some such, come forward and collect your prize!

I'm no transmission guy; they never interested me much, honestly. I much prefer any/all other parts of these cars to repair/rebuild and have done so many a time.
Even so, this answer does satisfy me that the usual logical progression of eliminating what a problem ISN'T eventually leads to what it IS.
It did so in this case, certainly.

We'll swap out the transmissions Monday and get the Passon unit on its' way back to Jamie and hopefully the car behaves itself after that.
Fingers crossed.
I need for it to work; really need a break here.

You going to the Chattanooga thing in May?

Hmm. Call me a skeptic but I'm still uncomfortable with that being a bearing noise. I guess we will see.

Did they drop the cluster gear and look at the pin ? If f that trans was run with ATF at anytime in it's life then there will be wear on the pin where the bearings ride , since the trans is apart it makes zero sense to not replace every bearing inside it.

I'm also going to ask the dumb question, has the bellhousing run out been checked , if that bellhousing is not the one original to that engine block there is not guarantee it's within spec.

Yes, there are two "Main bearings" one on the input shaft and one on the main shaft. The front bearing is probably a 308 bearing in your case "pun intended" and the rear is a 308. I would like to see how the bearings spin and how they look. If that's the case, cool replace and drive it. I would put a fresh set of gaskets on the side cover and tailshaft while its apart. They are cheap. There are different thicknesses of the 308 bearing, make sure you get the correct one. On the back of the input shaft there are needle bearings where the main shaft mates to it. Have them inspect those to make sure they are in good shape.

Also What JohnRR said....

307 in the rear ?

I just assumed the EXPERT rebuilding it would use new gaskets but now it sounds like it's going to get slapped back together with RTV ... ugh

No idea at this point. Guess it depends on this.

No idea and no idea, sorry.
Re: bellhousing, it's an original '68 one and the engine block is a '72, so there ya go. I've never been a "pull out the micrometer and index the bell to the thousandth" kind of guy - if the tranny slides in properly, then it's close enough for me.

You assume much and know little, but thanks for ummm....something?

Again, the trans guy has the unit, not me. He's the pro; I am not. I won't be there while he's rebuilding the unit.
He comes well-recommended by local mechanics.
Other than that, the plus to doing things this way is obvious:
if it turns out something isn't right, the recourse is very local - and I gets my recourse when it's warranted.

I can only go off the gibberish you've been posting ...

You seem to be the only one having difficulty - and you also seem hellbent on making snarky comments instead of actually offering useful advice, too.

Seek help.

Conclusion:
The GTX is all back together as of this evening. The repaired transmission performed flawlessly on the trip home, which coincidentally was the first time since I've owned the car (over 7 years) that it was driven in the rain.

The decision was also made to resurface the flywheel due to indications of premature warpage (probably came from the supplier that way). We also installed the roller input bearing in place of the usual bushing.

The Passon unit has been repacked in the original crate and will be returning to Jamie once he forwards the necessary documentation to do so.
Chalk it up to stuff happening sometimes...

The local transmission guy is apparently correct in his diagnosis and repairs to my original transmission. An extended road test once this storm front is finally gone will finalize confirmation of that.

I appreciate all the advice and help offered by several folks in this thread!
That said, I won't bother next time. There's a few bad seeds in this forum that need eradicated, sadly. Nobody needs to be badgered while seeking help and I'm pretty sure that's not the point of this forum.
Darn shame - this website has been around longer than most.

What was the problem? I just read a little higher and I see it was the Bearings.

I’ve seen these threads with similar answers for years and years. Had my own go that way. No reason to throw your hands up. Wasn’t even a big deal what was said anyway. If you want to quit over that, I’d say we just watched the weak get killed and eaten. And this isn’t even the Bullet!

Yessir.
Those who guessed "bearings" step forward and claim your prize!

It's one thing to be irrelevant in posting on forums; it's quite another to be a horses' ass just for the attention whoring.
That sort of childish, immature schoolyard nonsense neither serves to amuse nor does it offer anything of use to the conversation.
A lot of folks just blow it off when someone shows their ignorance like that, which leads ultimately to some extent to the degradation of society as a whole; we become more and more desensitized and we're less and less apt to be decent to one another.
I'm the kind that confronts it.
Have been for many a decade now.

Good luck with that. You should buy some rental property and set the fools straight there too!

Did your shop give you the old bearings? I would REALLY be interested in an inspection of the defective bearing. I am still struggling with the bearing being the culprit even though it now seems to be obvious.

I am interested in seeing the bearing as well.

It may have had a bad bearing, but my bet is the bearing was causing a vibration causing something else to make that buzzing sound. I've never heard a bearing sound like that either.

So who we dealing with here, John Wayne, or Johnny Rambo?

Bad seeds and Have been for many a decade now. Whats with the cheesy movie lines?

Whats next, a line from a Hank Williams Jr song?

Come on, go toss your box of old vhs tapes, cassettes in the dumpster and get out and live a little and LOOSEN UP while your at it.

But glad ya got your car fixed, now we can all sleep better at night.

what movie lines did he quote? Johnny Rambo? must have missed that one

Keep in mind, I was there for the whole re-installation of the unit and did some of it myself.
I had the bearings in my hands at one point, then tossed them out.
The rear one was fairly rough; I played with it for a while.
Again, I defer to the knowledge of the transmission guy - and the trip home was uneventful, too.

The car will get an extended drive this weekend. We'll see.

Me too, since I didn't.
Never liked the Rambo movies much, either.

I happen to concur.
The theory developed on the scene was that the roughness of the rear bearing caused it some manner of "galling" (for lack of a better descriptor) at speeds above 45 or so - and that when this galling occurred, something else (likely the shifter adapter plate we found slightly loose) or some such commenced to vibrating and making the buzzing sound.
Whatever it was, it was totally gone on the drive home and the transmission shifted as beautifully as it ever had.
We'll see with longer drives...