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I have a 81 auto that the rear diff has gone bad, going to replace it with a 81 manual rear. What problems am i going to run into? Don't want to remove trailing arms, looks like u-joints are bigger in the manual when looking them up. I have the complete rear in my manual parts car. I believe everything is heavy duty in the manual rear assy. There's no part of a car I haven't replaced in my 60yrs, but this is my first Corvette
I have a 81 auto that the rear diff has gone bad, going to replace it with a 81 manual rear. What problems am i going to run into? Don't want to remove trailing arms, looks like u-joints are bigger in the manual when looking them up. I have the complete rear in my manual parts car. I believe everything is heavy duty in the manual rear assy. There's no part of a car I haven't replaced in my 60yrs, but this is my first Corvette
Any help would be appreciated
Welcome to the forum. Here are links to some fairly recent threads discussing differential removal: You should find some good info there.
The actual differential, carrier, batwing and internal parts are the same on manual and automatics on the 80-82 Dana 44's. NOW here is the difference, the u-joints are larger on the manual setup than the autos. This means that the stub axles, half shafts and spindle flanges are different due to the larger u-joints. You can change out the stub axles back to the automatics with no problem, the are internally the same where they go into the carrier itself, just the u-joint part of the stub axle is different. Or if you want the heavier duty parts from the manual setup, all you would have to change would be the stub axle flanges to the ones from the manual car if you didn't want to change trailing arms. I did this change on my 81, used everything from the manual car, no problems what so ever making the change. They do mount to the side frames completely differently than the 79 and earlier cars. Just mounting tabs, no sombrero mounting points to fight with. The front differential mount is the same though.
Last edited by MattoonVette; Aug 26, 2021 at 03:34 PM.
The manual stub axles use 5/16 bolts instead of the 1/4 inch used on the automatic stub axles. If you are making more than stock power a good upgrade is to run a cap instead of the stock straps.
The manual stub axles use 5/16 bolts instead of the 1/4 inch used on the automatic stub axles. If you are making more than stock power a good upgrade is to run a cap instead of the stock straps.
81 Differential Swap
