Big Dummy 727 disassembly question

If you have to pull the front clutch to add springs (going from 12 to 15), how close are you in disassembly to go ahead and replace the low/reverse band while it's apart?

This wouldn't be work I would do myself; trying to get a sense for how much more expensive to do the second job if I've already committed to the first.

Thx - Brad

20 minutes, 30 min tops plus price of band. but i would check clutches/clearance in other drum also.

About 5 minutes tops.

Pull the front and rear clutch out as an assembly. Remove the snap ring holding the geartrain in place - then slide all the components off the output shaft. Loosen up the rear band adjuster, remove the link and band, install the new band and link.

Install the geartrain.

Done.

I wish I was more trans savvy, but about all I can claim is to have watched over Jim Hanrahan's shoulder as he went through mine 10++ years ago. I'd really hate to eff it up trying to save the $$$...

The front and rear drums come out as an assembly. With the trans out of the car less than 30 min if that... Do yourself a favor and purchase Torqueflite A-727 Transmission Handbook written by the late Carl Munroe. You will giggle the next time a trans guy tells you "1200 bucks for me to go thru your trans".

I recently took a peak inside my 904. I have never done any trans work either beyond a valve body change. Everything looked good inside and I went ahead and upgraded the clutches and steels and did the necessary work for this trans brake I am adding. It wasn't as scary as I thought it would be. Now the real truth will be if it works when I install it this weekend!

i too like to do a 727,from what i here there not bad

the 727 and 904 are the easiest transmissions there are to rebuild. if i can do it, anyone can. [well, almost anyone. ]
the hardest part is the disassembly and reassembly of the valvebody, [just pay attention] and if a guy can do that, the rest is cake.
as said, get the monroe book. and for extra help, get an ATSG [Automatic Transmission Service Group] manual, available many places for $20-40.00.

The trans is out and I already have the Munroe book.

My original plan:

1. Change from my current Turbo Action FMVB (no LBA) to the CRT RMVB (LBA) I purchased last year; I need to add 3 springs to the front clutch pack per John C; also need to put a Shift-R-Gate in my Slap-Stik shifter for the RMVB

2. The front clutch pack clearance from when Jim built the trans is on the loose side for what John likes to see, but said it would probably be close enough to use; still, if it's apart and can be tightened up a bit (not that I have -- or know what specific -- parts are required to do this), this would be the time

3. If the guts have to come out of the trans, I might want to replace the used low/reverse band that Jim & I decided to put in when he went through the trans for me; we got caught w/o a new one not expecting my old aftermarket one to need replacement, and Jim dug out an "OK" condition used band OEM for the sake of getting it back together while I was there


OR, the Quick-N-Dirty approach:

1. Pull the Turbo Action VB

2. Put in a front clutch passage restrictor to tame the 2-3 shift at part-throttle/lower RPM

3. Put the Turbo Action VB back in and be done w/ the trans "for now"


I know how things go w/ me... if I take the Quick-N-Dirty approach, "for now" means the trans won't come back out for the other upgrades until it either starts slipping from normal(?) wear & tear or I damage something and am forced to pull it back out of the car.

Deci$ion$, deci$ion$...

For the amount of time it takes to tear it down now its worth the time... just do it

Pick up a new pump to case gasket, and 7 new pump to case bolts or gskts.

Call Cope and order a thicker snap ring for front drum. If your snap ring is already thick maybe install an extra steel, and a thinner snap ring. Also order new low/rev band.

I'll look through the C. Munroe book and see what sort of tools are required, how much of a clusterf**k I'm likely to make of it, etc.

A friend agreed it would be good to learn, but asked if I have time for what looks like another project. It's that age-old time vs $$$ dilemma.

Thanks to all who replied.

The only thing special you will need is a spring compressor for the front clutch if you decide to add more springs. I just bought one from amazon for cheap and it worked pretty good, should be even easier on the larger 727 parts.

Winner! Winner!

I don't have time for the trans to become another project by itself, and there are still "must do" things to pay for that take priority over upgrading the trans at this time.

Good Call!

No need to upgrade if it was functioning OK. Just maintain what you have. Not much time or money to maintain the thing if it's not hurt. In the shop on the bench? If the pump is coming out, I'm going through it, clean it up, look at everything, maybe reseal the clutch packs. It would be 100% when it went back in. Don't understand fixing something at the rear band and putting the rest of it back in without at least looking at it.

Take care of it and you rarely have to worry about having to deal with a pile of burnt up junk.

I took that as he is leaving the rear band alone and just trying to soften up the bang of the 2-3 shift.

Yep.

OK. Springs will change the timing of the shift. A seemingly hard shift can be the result of a hard high clutch apply or overlap. Two different issues.

How to tighten the high clearance depends on parts used initially and how much it needs to be tightened.

Don't sweat it if you have to do it yourself. I had a tranny shop local tell me some high amount and said they are a pain in the A** to do. My boss has been a mopar guy for a long time and constantly blew trannys up in his mopars. It had been awhile but he said just make sure you have a big clean area to work on it and go slow. I got this book: https://www.amazon.com/gp/product/1613253354/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 Plus I talked to A&A Transmissions on what parts to get for it and to beef up or change while I had it out. I was scared doing it and nervous but now that it done it runs killer and shifts hard.

The books mentioned are ok, i have them all. But this dvd rules for the assembly and disassembly work.

^^^ where do you get it & I'm assuming there is one for the 904

Fleabay

The rear band almost never needs replacement. The wear factor on one is minimal. The toughest part of the entire deal is replacing the front clutch piston seals and cleaning everything.
Doug

....or finding that magical pump that the gears are actually in spec.

Is any one making and selling a complete new front pump assembly?

Cool, I like video help. 727 rebuildThis helped me tremendously and it's free on youtube

If anyone wants I have that 727 Video. Send me your email address and I will send you a link thru Gmail to download it....dont have dial up.....lol

It will walk you the rebuilding...and the guy speaks perfect English....

Tony, PM sent.