Twin_Turbo

Some more pics and info. The 2 differentials are remarkably close in dimensions. The batwing on the older one looks to be a lot deeper w/ more "offset" but looks are deceiving. the stub axles on the c4 one are only about 3-4mm further back. I will install it like that, my wheels are a little further back anyway because of the L88 flares and how they move the wheel arch back a little. The batwing width differs by 1cm on each side for a 2cm total (1 cm = .39"). I'll probably install some offset bushings in the batwing, those stock rubber ones are coming out anyway. Then it's a simple bolt on job with only a pinion mount to be fabricated. I'm going to remove the stock pinion mount from the frame (I gusseted it already..lotsa cutting there now) and will bolt the c-beam pad tight with bolts from below threading into a mounting flange on top that will weld to my subframe structure in the rear. Normally a pinion mount would easily be made, probably easiest by modifying a pre 80 one from a cast iron diff.

Only downside is, I'll have to redo the whole camber bracket and toe control plate also. I'm not going to use the stock C4 toe control center mount, the position is not right (long rods for reduced angular effect, I want mine spot on in line w/ the u joints)

some pics, left is the 82 diff..the dirty one w/ the rustuy stubs is the c4 one.

comp

going to have fun reading good pic's

norvalwilhelm

Marck where does the strength come from with the C4 as compared to the C3??? I did notice the yoke flanges are bigger but what else??

Twin_Turbo

The yokes are the same size, 1310s on the pinion and 1350s on the stubs, the pinion gear shaft is larger in diameter and there's just so much more meat in the case around the pinion area. By looking at the batwing you'd think the c3 one is stronger but it's not.

Also the main caps are much beefier on the super dana44 and the case is actually machined, as are the caps. on the C3 one it's as cast surfaces!!!

The C3 differential problems are in the case, they tend to break out the entire side of the pinion area.

norvalwilhelm

Thanks Marck. Gary offers a steel cap for the carrier with upgraded 1/2 inch bolts. Next winter I will upgrade with parts from him.

Twin_Turbo

I think Gary got the cap from toms, but those caps are not for the aluminium differentials.

I got the diff partially installed, modified the frame mounts to get the bolts in the right position (will have to gusset it up and add some more meat, the bolts are close to the edge of the mounts now), I will mount the pinion side like in the 2nd pic, just a little beam there w/ a plate that has threaded holes, that way it only takes 2 long bolts from the bottom to tighten up the diff and it's height adjustable by shimming.

stickboy

Will the Super Dana 44 bolt to the C3's batwing? Is the C4 batwing stronger?

Twin_Turbo

No, the batwings are not interchangeable. That would have made bolting it up even easier. Same for the camber bracket, it's close but the "bump" on the bottom of the C4 one is itnerfering. The C3 one is perfectyl flat on the bottom.

The C4 D44 batwing is stronger than the D36 one, I have no info if it's stronger than the C3 one. The C3 one has more meat.