Well since my brother is a CNC machinist and I didn't want to pay over $1000 to have a reinforced differential I decided to put him to work. So I picked up a stock low mileage 4.10 diff to do some "testing" with before I reinforce the 4.77 diff that is currently in my car. This has been a fairly long process and we are finally making some headway.

Anyways, here's some pics of the progress so far...




Stock cap machined down and the steel reinforcement cap. Also in the pic the new, longer tab for the diff bearing "adjusters".





Very tight tolerance between the two caps










And my brothers own personal Makino 3-axis CNC machine



Gonna pick up some bolts tomorrow, go through the diff and put it all back together.

More to come....

 

nice... id get a new collar too... puddy mod will sell or js racing... but then u need to set back lash.. i have a comptech rear with a puddy mod colar... puddy mod built it for me... with 4.57

 

Nice!


How much do you have in that setup if you don't mind me asking?

 

Very nicely-equipped shop! I'm curious why no one has yet made new billet caps. I keep seeing this same Comptech-style bracing for the stock caps. Seems like a complete replacement of the cap with a billet piece would be stronger and an easier swap-out, since there would be no need to machine the stock cap to accept the brace.

Is your brother planning to reproduce and sell this mod? If not, maybe you could get the G-codes from him and make them available here. That would be a very nice contribution to the community, indeed.

Anyway, that looks like you have a very nice project going. Best of luck and keep us informed of your progress.

 

Well since the cap is threaded to match the diff housing it would be hard to match the threads up without machining both down and rethreading the whole thing. On top of that it would make setting up the pinion that much harder.

 

Where is the cap threaded? The two large bolt holes on the ends or the one small one in the center?

Nevermind, I re-read and now realize that the only bolt holes touching the housing are the two large ones on the ends. I didn't know they were threaded. THanks.

 

I guess you didn't put threads in the new brace then? Guess that's why the shoulders for the bolt heads are countersunk so deep, then.

I wonder how the factory matches the threads between the housing and the caps?

 

Sorry for the confusion, this is the threaded part I was referring to...

 

have you looked into puddymod's diff builds?

 

Yes, as indirectly stated in my first sentence.