Alu OD 833

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Cuda416

Cuda416

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Anything to watch out for specific to aluminum OD units? It's not going into a drag car, just a daily driver.
 
Yup. Make sure it's not ta truck transmission.
 
RustyRatRod said:
Yup. Make sure it's not ta truck transmission.
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The guy claims its a 75, for an A or F body. I've not see the tail housing yet. I've asked for pics. My understanding is the truck version has the dual shifter pad configuration, right?
 
Cuda416 said:
Any particular reason why?
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Yes. The shifter location is in the wrong place. They have a dedicated shifter location. The B and E body transmission has the dual shifter mount pads.
 
.........Plus the truck/ B/ E body tail housing is too long .........

You always get hits that the aluminum boxes wear out the cluster shaft boss in the aluminum housing, so check that out.
 
Do you get the bell housing with this deal also, cause it would have the large hole needed to mate with the front bearing housing of the O/D unit.
 
Woah, lots of good info, thanks everyone.

@RustyRatRod, good to know, thanks!

@72bluNblu, man I forgot about that 4 speed trans info page. Never saw the other right up on the adapter plate, that's awesome, thanks!

@67Dart273, That's great to know and something I'd have missed for sure.

@Max1196, the bell housing isn't part of the deal, i wish it were.
 
I learned something guys. I need to check mine to see which one I have.
 
Cuda416 said:
The guy claims its a 75, for an A or F body. I've not see the tail housing yet. I've asked for pics. My understanding is the truck version has the dual shifter pad configuration, right?
Click to expand...

F bodies started in 76.
I've pulled both aluminum and cast iron OD 4 speeds from F bodies.
probably still have them.
You'll need the 5.124" retainer opening bell.
pn# 3743859 WITHOUT the insert ring
 
Jimacuda said:
F bodies started in 76.
I've pulled both aluminum and cast iron OD 4 speeds from F bodies.
probably still have them.
You'll need the 5.124" retainer opening bell.
pn# 3743859 WITHOUT the insert ring
Click to expand...

Good to know. My guess is he is saying it's from a 75, but will fit A or F. Still haven't seen the tail housing. Hopefully later on today.
 
Earlier the better. 75 "A" body or "F" body should be good, shifter and all. If you are lucky, it is possible to get one with the smaller 307 front bearing. Then all you have to do is swap the front bearing retainer. The aluminum main housing has a floating countershaft, read sloppy, that can loosen up even more with usage. Try it and find out how she runs. Dump the ATF and put in 90 wt gear oil. I skip to a 64 or 65 cast housing and a new 64-65 countershaft to get everything tight again. Good luck.
 
66fs said:
Earlier the better. 75 "A" body or "F" body should be good, shifter and all. If you are lucky, it is possible to get one with the smaller 307 front bearing. Then all you have to do is swap the front bearing retainer. The aluminum main housing has a floating countershaft, read sloppy, that can loosen up even more with usage. Try it and find out how she runs. Dump the ATF and put in 90 wt gear oil. I skip to a 64 or 65 cast housing and a new 64-65 countershaft to get everything tight again. Good luck.
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I dunno about that. The 308 bearings came about for a reason, they went to the larger bearing to help make up for the 3-4 gear reversal changing how the power was routed in overdrive (3rd gear on the cluster).

You can buy a 4.8" diameter bearing retainer for the 308 bearing cases (or turn the 5.125" retainer down to 4.8"), and then you can have the 4.3" bellhousing machined out to match the 4.8" retainer. They sell the 4.8" retainers with the bolt pattern for the 308 bearings now, makes putting one behind a big block easier. More info on that on the bottom of this page, they turned it down but I've just bought the 4.8" bearing retainer with the larger bolt pattern since then

Mopar Big-Block A-Body 4-Speed Conversion
 
And if the loose front cluster pin bothers you you can get a bushing made up at the local machine shop. But for a driver, I wouldn't bother. They shift fine with lightweight gearoil. In a low-powered unit I prefer ATF . I run 50/50 in mine and drive the berries off it with about 400hp. The only reason I put 50% EP oil in there was cuz I felt sorry for the clusterpin. And it didn't shift that much slower after it warmed up,lol.
Myself I like the longtail cuz; A) it was a direct fit with the bigger 727 sized mainshaft, and the 727 driveshaft, and B) the shifter pad was further to the rear, and I installed it yet further back, between the buckets.
The A/F's I bought had the smaller 904 sized output shaft, and I didnathink they were good to 400hp. But for your stated useage that shouldn't be a problem.

That trans works very well with a hi-torque,low-rpm engine, and about 3.23s, but not much more than 3.73s, else you will be shifting into second almost right away. Nor any less than 2.94s cuz then second will tank, which is worse.
4.30s sucked big-time. 3.91s were good for a peppy second gear.I liked 3.55s the best, cuz I had enough torque to pull them and 65 was 2100; and my little 223*@050 cam was ok there.
 
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72bluNblu said:
I dunno about that. The 308 bearings came about for a reason, they went to the larger bearing to help make up for the 3-4 gear reversal changing how the power was routed in overdrive (3rd gear on the cluster).

You can buy a 4.8" diameter bearing retainer for the 308 bearing cases (or turn the 5.125" retainer down to 4.8"), and then you can have the 4.3" bellhousing machined out to match the 4.8" retainer. They sell the 4.8" retainers with the bolt pattern for the 308 bearings now, makes putting one behind a big block easier. More info on that on the bottom of this page, they turned it down but I've just bought the 4.8" bearing retainer with the larger bolt pattern since then

Mopar Big-Block A-Body 4-Speed Conversion
Click to expand...

So you want to buy a 4.8 retainer, bore the bellhousing to match the 4.8 retainer, and hope that all the machining is spot on? No thanks. I've done this too many times to worry about the 307 bearings. By the time I tighten everything up and have the stronger cast iron case with 90 wt gear oil, I'm good. I haven't worn one out yet, and I've been running one since the late 70's. I can simply slip my O/D in place of the 4 speed, hook up the shifter, and am good to go with easy stock parts that I can put back to stock whenever I want.
 
66fs said:
So you want to buy a 4.8 retainer, bore the bellhousing to match the 4.8 retainer, and hope that all the machining is spot on? No thanks. I've done this too many times to worry about the 307 bearings. By the time I tighten everything up and have the stronger cast iron case with 90 wt gear oil, I'm good. I haven't worn one out yet, and I've been running one since the late 70's. I can simply slip my O/D in place of the 4 speed, hook up the shifter, and am good to go with easy stock parts that I can put back to stock whenever I want.
Click to expand...
Refresh my memory, is it the 3-4 shift lever that you invert?
 
On a drive-on hoist, I can actually RnR an A833 faster than a rear chunk.
My personal best was 17 minutes to; pull the drainplug, Pull the shifter,drop the TTIs,drop the driveshaft, unbolt the GVOD,and finally, drop the aluminum-boxed long-tail A833.
But I cheated a bit;this was the third time In about a week and all the tools were still on the tool-cart. Third time was a charm, after that it shifted at 7200 with very little effort............ like a Ford, ptouii
 
I went through some of this recently as I gather parts for my E body swap. Some consider the OD less robust because the counter shaft has clearance in the case, but this can be bushed. Some don't like the 3.09 first gear. Supposedly the throwout fork assy on the original OD bellhousing is different somehow than standard A833 housing. A standard 4.3 or 4.8 bell housing apparently can be opened up to work with the larger 5.12" retainer on the OD trans, but probably smarter to cut the retainer down to 4.8.

There is a lot of good information here
4 Speed Transmissions transmission
 
The 3.09 is sorta the best part of that swap, but it sure makes for a looooong 1-2 split. The 3.09 lets you run 16% less gear in the back for the same take-off power. But if you do that , then you lose ~25% on the shift into second. Here's how the ratios compare;
2.66-1.92-1.40-1.00std box, versus 3.09-1.67-100-.73od.
If you were using 3.73s with the 2.66box then your final drives would be pretty sweet ratios of;
9.92-7.16-5.22-3.73with the standard box
To get the same starter gear with the od box would require ~3.23s. Your new final drives would be;
9.98-5.39-3.23-2.36 with the od box.
Now compare the second gears; 5.39/7.16 =.753 or a loss of TM in the amount of 1-.753= .247 or ~25%. with the od box. So a better idea might be to make second gears the same, ie 7.16. That would require a rear gear of 4.30s. And you get
13.29-7.18-4.30-3.14with the od box. Of course now you have a drag-race starter gear. And third gear is way out there again..Since nothing works really all that well, you can split it up the middle, running 3.73s again. The new final drives would be;
11.53-6.23-3.73-2.72with the od box. This is a reasonable compromise, if your engine likes to cruise at 65=2200
So IMO, this is a very wide ratio trans, but suitable to be used with an engine designed to work with it. That generally means a hi-torque lo-rpm engine.... like stock 318s and slantys.
A 360 will pull it just fine with a small cam. Or at least one with an early closing intake valve to trap the pressure.
There is a guy here on FABO running one with a 340. I forget what cam,maybe a 268, but he says he's happy.
I can tell you for sure it sucked with a 292/108 cam in my 360 @11.3 Scr.
I can tell you for sure that with a 270/276/110 Hughes and now at 10.9Scr, it was sorta bearable. But I bought the GVOD PDQ, to start splitting gears cuz the splits in the od-box were just too far apart at high-rpm, for my combo. That gave me 8 usable ratios. But having to split ratios in traffic proved to be the death-knell for that combo. I was done with it.
I swapped that box out for a 3.09 early Commando box, plus the GVOD still; 3.09-1.92-1.40-1.09-.78od; splits of .62-.73-.78-.72od : prettysweet. That combo has been in there now since 2004.

For OP in a DD, the 3.09odbox will work just fine.
 
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