Mopar 4-speed overdrive

[whayden2003]

Ok. School me on what the heck this is. Says it was from a truck. 4-speed overdrive?
23 spline. Aluminum case. Long tail housing. Opinions. Junk??

 

[PurpleBeeper]

I think pictures and/or numbers off the transmission would help. I'm not a transmission expert. I thought that aluminum case A-833's with overdrive were from Feather Dusters and Dart Lights, not trucks.

 

[whayden2003]

Yea. I botched getting pictures when I was there. I was a little quick on the tread posting gun I guess.

 

[rumblefish360]

The OD trans came in aluminum and steel. The length is short for A body car use so installing one in a B or E would require some thought and measurements. There retainer is large. This requires modifying the retainer or bell.

Hey m not sure exactly on how it goes.

I have one so if you want some tape measure work done, let me know.

 

[multimopes]

I had a steel one in a 76 Volare' wagon with bad sincro's. Bought a used one with an aluminum housing from an Aspen wagon for $50 and the rear tailshaft seal was shot. It worked fine though. They were used in 1/2 ton 2 wheel drive pickups also as I saw one in a bone yard. I think it had the long tail for that application. There was a plastic tunnel extension that screwed to the floor to give clearance for the shifter if I remember correctly. I also remember that the shifter knob thread was reverse threaded which pissed me off as I wanted to put a Hurst Tee handle on it. I ended up rethreading the shifter so I could install any conventional handle. Worked nice!

 

[whayden2003]

Wonder if it would last behind a 400 built pretty stock.

 

[multimopes]

I don't see why not, just don't hammer it too much. The gear ratios are weird and not meant for performance on a stock unit. Having overdrive is nice though, really helps drop the rpm's at cruising speed!

 

[toolmanmike]

Don't quote me but I think the counter shaft bushings on some are just machined into the case and not a brass bushing or bearing.

 

[mopar 3 B]

Don't quote me but I think the counter shaft bushings on some are just machined into the case and not a brass bushing or bearing.

Counter shaft bushings? You mean these don't ride on needle bearings? Retainer and input shaft bearing are same size as hemi units.

 

[rumblefish360]

There are a few problems with the OD unit. I described 1 already with the bearing size retainer. Length is the other one.

After those of which I mentioned, the folk law of it being weak is another problem of which it is not BUT high hp is not what I’d put in front of it. How much it can actually handle IDK. But the next problem is mostly in the ratios of the gears. 1st is super grand am near useless. 2nd & 3rd are normal-ish and 4th is a heavy drop again as many complain about.

4th gear also rides (and resides) in the 3 gear spot not the normal 4th gear spot. This seems to be a problem with a lot of people and high horse engines.

I personally don’t see a problem with 400 or 450 hp or lbs. of torque.

 

[YY1]

I have two.

They are the same dimensions a B/E trans.

The retainer is large and can not be milled down as some will tell you, because the bolt circle pattern is also larger. The confusion comes from a retainer with the same outer diameter but a smaller bolt circle that was in other applications.

Bell housings for the large retainer are available for SB, and I know a BB application is possible because I have one in a running driving 440 powered truck. The bell in that is iron, but I have not had them separated to see how they did it.

That particular 440 is a 1969 10:1 and sounds like it has a moderate cam installed.

It has been fine so far and I do drive it as a 440 4 speed was meant to be driven.

I am not sure what axle gear is installed, but I will say 1st gear becomes useless real quick, and I spend a LOT of time in second.

 

[whayden2003]

Thanks. I'm not looking for perfection in gearing. Not drag racing the car. Just want to cruise. So the weird gear jumps will not bother me. Especially since I haven't experienced a non OD A833. I'm wondering about the passon gears for it. Prolly get close to just getting a regular A833 trying to make the OD A833 perfect. Still researching.

 

[rumblefish360]

I have two.

They are the same dimensions a B/E trans.

The retainer is large and can not be milled down as some will tell you, because the bolt circle pattern is also larger. The confusion comes from a retainer with the same outer diameter but a smaller bolt circle that was in other applications.

Bell housings for the large retainer are available for SB, and I know a BB application is possible because I have one in a running driving 440 powered truck. The bell in that is iron, but I have not had them separated to see how they did it.

That particular 440 is a 1969 10:1 and sounds like it has a moderate cam installed.

It has been fine so far and I do drive it as a 440 4 speed was meant to be driven.

I am not sure what axle gear is installed, but I will say 1st gear becomes useless real quick, and I spend a LOT of time in second.

That B/E length is from a truck?

 

[YY1]

...and they have the same shifter mount locations.

 

[YY1]

The other iffy thing about the pattern is that power shifting 2-3 is not terribly fun, however, the spring in my factory Hurst shifter is really nice at guiding it over.

 

[whayden2003]

Yea. I want to say it was the b body length for sure.

 

[whayden2003]

The other iffy thing about the pattern is that power shifting 2-3 is not terribly fun, however, the spring in my factory Hurst shifter is really nice at guiding it over.

Yep I got my factory hurst shifter for the car too. Only thing I got right now to hold on to and make potato potato noises. Lol.

 

[HawkRod]

I have one in my 1970 Road Runner (my original 4 speed is untouched on a shelf). Jamie Passon of Passon Performance built it for me for my drive across country. It swaps perfectly with my factory 4 speed with no modifications of any kind except flipping the 3rd gear lever. It is a temporary unit while I wait for a A-855 transmission.

The ratios on my overdrive are: 3.09, 1.67, 1.0, 0.73
Compare this to a standard 4 speed: 2.66, 1.91, 1.39, 1.0

The good: It makes highway driving really nice. My car has 3.55 rear ratio, and spending hours in the car without an overdrive gets loud and tiring. With the O/D, you just cruise along comfortably. Also, it delivers better gas mileage.

The bad: As you can see above, the ratios are NOT built for performance. My experience is it kind of "neuters" the performance of the car.

My personal verdict: If you do a lot of highway driving, get one - they are great for that. If you plan to just drive around town, I'd stick with the standard 4 speed - you lose too much fun with the O/D.

Hope this helps...

Hawk

 

[rumblefish360]

@YY1

That B/E length is from a truck?

 

[YY1]

I don't understand your question.

yes, I believe the B/E 833 and the truck 833 O/D are the same case dimensions.

If that's what you're asking.