Thanks Gary for taking the time to provide all this info.

Bandwidth ? I took all the differential related photos from Stinger12's thread and copied it all in a word doc so I have all that info whenever I take mine apart. I din't know at the time he was going to do the same thing.... btw, is he here yet ??
This word doc is like 80 pages and 20MB..... just in case somebody wants to host it...I'll have to upload it or send you a CD....:lol:
I found this boat anchor very cheap. I bet if I hit it with a hammer it would put a hole in the case. Remarkably it turns smooth as silk. When I get it apart I will save the internals. Gary keep up the good work. I enjoy your posts they are never boring.

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:thumbs: Thanks Gary........I really appreciate the time and trouble you put into those posts to help the rest of us............ :)
Up next. SMYDA"S corner. Coming soon I hope.LOL

:confused: :D

I'd be happy to contribute ......... Just give me some time ....... :)
5 kids ..... 1 income ........ Too many projects .......things don't
happen near as fast as I would like ..... sure you understand :wink:

In the mean time I'll transfer any topics of interest I posted elsewhere
to here ........ just let me know. I plan to do the crash manuals tonight.
I've got a couple of those 82 diffs lying around. Maybe do an article on those sometime (or better yet, have Mike/tracdogg do it :) I've got plenty to do as it is )
I don't think I have ever seen an explanation of the difference in diffs from C2 to C4. C2 and early C3 are not as strong as later C3, 80-82 are not as strong as iron C3, C4 Dana 44 is more desirable than C4 Dana 36.:confused:

It would be kinda nice if someone would do a quick writeup on the relative strength/weakness of these diffs. I know I'm confused.
The C4 Dana 44 is actually called a super Dana 44 and it uses the same ring, pinion & carrier as the viper unit. The only difference is the case.

The super Dana uses a Dana 60 sized pinion, where the C4 D36 & the C3 D44 both use the smaller sized pinion. These 2 use the same sized pinion but different sized ring gears. The carriers are even interchangeable (I have a C3 D44 w/ a C4 D44 carrier with the 8,5" ring gear)

C3 D44
Pinion Shaft Diameter: 1.375"
Pinion Spline Count: 26
Ring Gear Diameter: 8.5
Ring Gear Bolts: (10) 3/8 x 24 RH
Cover Bolts: 10

C4 D36:
Pinion Shaft Diameter: 1.375"
Pinion Spline Count: 26
Ring Gear Diameter: 7-9/16"
Ring Gear Bolts: (10) 3/8 x 24 RH
Cover Bolts: 8

C4 D44 HD/V/Super
Pinion Shaft Diameter: 1.625"
Pinion Spline Count: 29
Ring Gear Diameter: 8.5
Ring Gear Bolts: (10) 3/8 x 24 RH
Cover Bolts: 10

The C4 D44s are not all alike either. Supposedly the early housings are stronger. There are 3 versions, the differences can be seen by the ribs in the C beam pad and the other stiffening ribs. The early batwings are stronger also.

The C4 D36 is easily identified by that it has a single top mounted cover bolt, the 44 has 2 bolts on the top, much like the C4 unit.

the C4 and C3 housings and batwings are not interchangeable between either C3 D44, C4 D36 and c4 D44.

The camber brackets for the C4 (2 separate pieces) will bolt up to the C3 unit, the C3 unit's single large bracket will not bolt up to the C4 unit because there's a bulge in the casting.

C3 D44


C3 D44 w/ C4 D44 case (see no c clips to retain center pin)



C4 D44


C3 vs C4 D44


3 versions of the C4 D44 case




The C3 D44 case, including measuring pinion depth and a case spreader.




A C4 D44 with a spool


Another thing to note is that the C3 D44 uses CAST bearing caps and that the housing is NOT machined for the cap seating surface, it is AS CAST.

The C4 D44 does have machined surfaces and the caps are forged aluminium. I'm not sure about the 36 though.

Another thing which is different between the C3 and C4, apart from the obvious that the C4 uses a C beam front diff mount, is that the C4 batwing is narrower (both D36 & D44), it's narrower by exactly 2cm. You can easily modify the 80-82 frame brackets, the C4 one will fit after you remove the 2 square alignment blocks.




The C4 differentials will NOT bolt up to the 80-82 batwing.

Here's a complete C4 Dana44 in a C3 with a custom pinion mount. The holes in the frame brackets were simply enlarged for fitting & testing purposes, later theyw ere changed for new fabricated parts.



Nice pictures of the Dana's. Looks like you have a nice work area as well.
Can you reference the pinion depth off the aluminum pads? I know the iron units can be off 020-030 from the pads top. I was going to machine up some bearing spacers to make up a dead center location but I just use the pattern method on the iron units.
It's just a quickie and fingers crossed way to set the pinion depth but a lot of times, it's off. If it works, you save some time, if not...oh well LOL In the end, the pattern and the backlash still dictate what you do shim wise.

The pics of the empty C3 D44 case do nicely illustrate the "ridge" against which the carrier side bearings sit. That's all that takes the side thrust. You'll see the C4 ones do not have that.

Oh, and not all of those pics are mine. The 3 D44 cases are not and neither are those of the empty case with the spreader on it. They are from member GEE, he actually taught me how to do these things with a lot of pics (sadly I lost a bunch of them in a puter crash, these were all that I had on a server somewhere)
Marck, You never cease to amaze me. A comprehensive answer to my question, with pictures, in a little more than a hour! Thank-you