Moparts

O/D Transmission ????

Posted By: Chi_Town_Runner

O/D Transmission ???? - 03/05/11 02:01 AM

Bear with me as I try to explain this.

I have a '68 RR 383 4-speed car.
I just acquired an A-833 O/D trans.

It's an aluminum case trans with a cast iron tail shaft.
The tail shaft has dual mounting bosses for the shift linkage. The forward mounting bosses are tapped while the rear bosses are there but not tapped.

While comparing the two transmissions, it seems that the rear mounting flange on the O/D trans for the cross member seems to be about 3” more forward on the trans tail shaft than my stock transmission.

Correct me if I’m wrong here, but after doing some research it seems that the tail shaft with the duel shifter mounting locations were for later model B/E bodied cars.

Would an A-833 with the duel shifter mounting bosses have a different rear cross member mounting location than my ’68 transmission would have?

Thanks
Frank
Posted By: RapidRobert

Re: O/D Transmission ???? - 03/05/11 02:35 AM

Quote:

While comparing the two transmissions, it seems that the rear mounting flange on the O/D trans for the cross member seems to be about 3” more forward on the trans tail shaft than my stock transmission.

I think you have an A/F body OD 4 sp
Posted By: BBCoronet

Re: O/D Transmission ???? - 03/05/11 02:50 AM

I think what you have is a truck OD trans.............
Posted By: Chi_Town_Runner

Re: O/D Transmission ???? - 03/05/11 03:12 AM


Quote:

I think you have an A/F body OD 4 sp





Quote:

I think what you have is a truck OD trans.............



Is there any way to tell what I have ???
Posted By: RapidRobert

Re: O/D Transmission ???? - 03/05/11 04:47 AM

measure the distance from the front face to the trans mount & it'd b in the archives
Posted By: 1_WILD_RT

Re: O/D Transmission ???? - 03/05/11 04:53 AM

68-69 had a trans mount further rearward than 70... Get a 70 B body trans crossmember & your in business...
Posted By: Chi_Town_Runner

Re: O/D Transmission ???? - 03/05/11 06:25 AM

Thanks guys.

I believe you have resolved my problem.

Frank
Posted By: RapidRobert

Re: O/D Transmission ???? - 03/05/11 06:34 AM

Frank what do you have
Posted By: moparmarks

Re: O/D Transmission ???? - 03/05/11 07:03 AM

I have several 833OD trannys. Theres 2 that I know of. The short shaft A-body and the long shaft that was in trucks which has the later B/E tail housing w/ dual shifter mounts.
If your thinking of put the OD behind your 383 take note that the OD's have the large 5-1/8" front hub. They did make a BB bell that fits both 833OD and 435/445 trannys but is very hard to find.
Posted By: Evil Monkey

Re: O/D Transmission ???? - 03/05/11 08:01 AM

One thing to keep in mind - the Aluminum cased OD transmissions have a known problem. They use a floating countershaft, and the aluminum hole that the countershaft goes in can wallow out (due to the soft Aluminum), which will eventually cause the gears to separate and cause a major failure of the transmission. I had this happen on an Aluminum cased 833 OD that was behind my 360, and the gears literally broke into hundreds of little pieces. The only options to prevent this are to install bushings in the case for the countershaft, or to transfer everything from the Aluminum cased tranny to an Iron case.
Posted By: Chi_Town_Runner

Re: O/D Transmission ???? - 03/05/11 04:19 PM

RapidRobert
After doing some searching it appears that this trans had the spool type mount which as shown on Brewers catalog. The side boss where the #s are stamped is unreadable.

MoparMarks:
I'm aware about the IBR being so large. After I look inside this trans to see if it's usable I'll get a bellhousing that has the 4.8 IBR opening and have my machine shop open oit up to 5.125

EvilMonkey
This is the one issue that concerns me. My car is mainly a cruiser so it doesn't get beat on (no power shifting) but because I'm in a small town I do a lot of highway driving so that concerns me.

This article explained what some of the issues are.
A833 article

I got this trans in trade for a carburator so I don't have too much invested right now. Thats why I'm doing my homework.

Frank
Posted By: feets

Re: O/D Transmission ???? - 03/05/11 09:28 PM

Do NOT open up the bellhousing. Why ruin (permanently modify) an expensive part? Turn the bearing retainer down to fit the bellhousing. It's a 5 minute process including setting up the lathe. That's what I did for my 833 OD. The bolt pattern on the retainer is the same as the non-OD pattern. There will be no problem with the big retainer being cut down.

Here's the pic I uploaded with transmission measurements:

Posted By: Chi_Town_Runner

Re: O/D Transmission ???? - 03/05/11 10:08 PM

Hey Feets!

You read my mind. I was just looking into turning down the 5.125 bearing but wasn't sure what was underneath the retainer and was not sure if the cut on the IBR would conflict with the bearing retainer bolt pattern.

Thanks for the attachment.

I owe you and about 30 other guys on this board

BTW, I may be in touch with you for some more tech advise on this matter.

Thanks
Frank
Posted By: mod5v

Re: O/D Transmission ???? - 03/06/11 01:05 AM

Just a quick note on bearing retainers. There was a 3sp in the 70's in trucks I believe that had the small bolt pattern(4.3"} for the early abody 4speeds that has the 5.125" index size. So I have a o/d bellhouseing with a 67 abody 4sp trany with a 3sp bearing retainer to match the trany and the bell. I also have a 4.8" bearing retainer that has the same bolt pattern as the o/d trany. Moral of the story is there is likely a bearing retainer made to fit whatever your combo you just have to do a little resurch.
Posted By: RapidRobert

Re: O/D Transmission ???? - 03/06/11 01:31 AM

Quote:

Moral of the story is there is likely a bearing retainer made to fit whatever your combo you just have to do a little resurch.

I'm a 904 guy but I had a mag somewhere w the diff retainers MP introduced way back that iirc they had one for the OD (5.125") case but was 4.8" dia & gotta pay attention to if a 307 or 308 bearing behind it. Way back I had a bell machined out to 5.125" & that eliminated part of the L bracket for the fulcrum but there was enough flat area of the "L" left so they drilled 2 mounting holes next to the ones that got (partly) eliminated w the OD increase.
Posted By: feets

Re: O/D Transmission ???? - 03/06/11 02:58 PM

There are off bearing retainers out there. Turning an OD retainer down is quick, cheap, and won't hurt anyone's feelings.
Posted By: Mike P

Re: O/D Transmission ???? - 03/06/11 03:50 PM

Just a couple of things I’d like to add. If you’re planning on driving the car hard(and why have a 4spd RR if you're not) I personally would not recommend it with the aluminium case 833OD. Besides the bearing problems I’ve had a couple of those with cracked cases over the years and am not real impressed with their durability.

Depending on the gear ratio of you RR you may not be real happy with the gear split between 2nd and 3rd gear. It’s pretty noticeable if you running something like 3.23 but not too bad with say 4.10s.

There are some cast iron case A833 ODs out there in both long and short tail shaft versions (the short tail shaft version places the shifter somewhere in between the shifter location of the 2 positions on the long tail shaft version). All the cast iron case units I’ve come across have also had the larger output shaft rather than the smaller one used in the aluminium case versions.

I’m not sure what the factory application of the cast case OD trannys were as the ones I’ve had were pull outs when I got them but I suspect they came from trucks.

All that being said I am currently running a cast iron case A833OD transmission between a Tri-Power 354 Hemi and 4.10 Sure Grip in a 57 Plymouth and I do tend to occasionally run it pretty hard . So far it’s held up very well and OD droping the effective ratio to approximately 3.00 makes it a nice higway cruiser.
Posted By: JohnRR

Re: O/D Transmission ???? - 03/06/11 04:33 PM

Quote:


Quote:

I think you have an A/F body OD 4 sp





Quote:

I think what you have is a truck OD trans.............



Is there any way to tell what I have ???



You have the truck/van transmission, the A/F trans only has one shifter mounting pad behind the trans mount. The factory moved the mounting position in 1970 so they only had to source one crossmember, the crossmember you need is the same one used for an auto trans. It can be a spool mount OR the standard rubber drop in mount, depending on the crossmember and I don't think there is a crossmsmber for the spool mount in a 70 down B body platform. You can either turn down the bearing retainer or buy one for the bearing the trans has , more than likely the 308 , and the BB bell size, it's the same retainer used on 70 up Big block 833's.

Sorry if I repeated what others said , lots of misinformation in this thread and people telling what to do instead of answering the questions , just another day on moparts
Posted By: patrick

Re: O/D Transmission ???? - 03/07/11 01:23 PM

Quote:

Just a couple of things I’d like to add. If you’re planning on driving the car hard(and why have a 4spd RR if you're not) I personally would not recommend it with the aluminium case 833OD. Besides the bearing problems I’ve had a couple of those with cracked cases over the years and am not real impressed with their durability.

Depending on the gear ratio of you RR you may not be real happy with the gear split between 2nd and 3rd gear. It’s pretty noticeable if you running something like 3.23 but not too bad with say 4.10s.

There are some cast iron case A833 ODs out there in both long and short tail shaft versions (the short tail shaft version places the shifter somewhere in between the shifter location of the 2 positions on the long tail shaft version). All the cast iron case units I’ve come across have also had the larger output shaft rather than the smaller one used in the aluminium case versions.

I’m not sure what the factory application of the cast case OD trannys were as the ones I’ve had were pull outs when I got them but I suspect they came from trucks.





FWIW, my '76 duster, build date 11/75 has a cast iron OD, and I bought it from the original owner with 50k miles on it. I think the cast iron vs. aluminum might be an age thing more than an application thing...

love it behind my slanty with 25" tires (205/70R14) and 3.23's, it would be a ball with a moderate built 318 or 360 (say something with a dual plane, headers, ~9:1 compression and a 218@.050 cam)....gear spread never bothered me.
Posted By: JohnRR

Re: O/D Transmission ???? - 03/07/11 03:07 PM

Quote:

Quote:

Just a couple of things I’d like to add. If you’re planning on driving the car hard(and why have a 4spd RR if you're not) I personally would not recommend it with the aluminium case 833OD. Besides the bearing problems I’ve had a couple of those with cracked cases over the years and am not real impressed with their durability.

Depending on the gear ratio of you RR you may not be real happy with the gear split between 2nd and 3rd gear. It’s pretty noticeable if you running something like 3.23 but not too bad with say 4.10s.

There are some cast iron case A833 ODs out there in both long and short tail shaft versions (the short tail shaft version places the shifter somewhere in between the shifter location of the 2 positions on the long tail shaft version). All the cast iron case units I’ve come across have also had the larger output shaft rather than the smaller one used in the aluminium case versions.

I’m not sure what the factory application of the cast case OD trannys were as the ones I’ve had were pull outs when I got them but I suspect they came from trucks.





FWIW, my '76 duster, build date 11/75 has a cast iron OD, and I bought it from the original owner with 50k miles on it. I think the cast iron vs. aluminum might be an age thing more than an application thing...

love it behind my slanty with 25" tires (205/70R14) and 3.23's, it would be a ball with a moderate built 318 or 360 (say something with a dual plane, headers, ~9:1 compression and a [Email]218@.050[/Email] cam)....gear spread never bothered me.



Definitely an age thing , the first OD 833's were in A bodies and they were cast iron case , I think when the feather duster and dart lite came out , 76 ??? , they went to an alum case to save weight for fuel economy.
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