Posi Case 3789812 gears fit in 3743833 Posi Case?

[Brandon 348/320]

I found and bought a correct 3743833 empty case off of ebay a few months ago that is the correct date code and 3.70 differential code I need for my 60 restoration. Since then I have been trying to find a rear end that I can swap the gears out of and put it in the empty case I bought. I have found a 3789812 case. Will those parts switch right over into the 3743833 case. The guy said that he has receipts showing that the unit had been rebuilt when he bought it in with a deal on a car. The unit has never been installed. I am not a mechanic by any means, would this be a hard transfer or can/would you put an after market unit in my empty case? Thanks.

 

[Don Jacks]

Check out the tuturial on these rears in the 58-65 car section,called rear end master.Since you will be transfering parts from one case to another, you'll onl y need a new crush sl eeve and pinion seal as far as parts go,plus some marking compound. The bearing torque,the pinion depth,and the backlash are critical,but not impossible to achieve for a beginner,and these 4 parts will walk you right through it.

 

[models916]

If you do it yourself, the case bolts that hold the halves together are Left threads on the later units.

 

[Don Jacks]

Since he's transferring parts from one case to another,he should'nt have to worry about taking the differencial case apart.

 

[Brandon 348/320]

I talked to the guy that I bought my empty case from in Chicago. They run a Corvette shop and he said all parts will switch out. So is he telling me the truth? He said they are the exact same case, just different numbers.

 

[Don Jacks]

Yes Brandon,he is.

 

[oldskydog]

Just bolt the 812 in unless you are doing a numbers museum type restoration.

 

[1961BelAir427]

Just bolt the 812 in unless you are doing a numbers museum type restoration.

You could always include the numbers (and date?) correct case with the car if that mattered to a buyer. If you're not selling then what difference will it make? Would save you a lot of time and money.....and the potential of not getting it set up right.

 

[models916]

There is an early and late posi unit. Not the housing but the Positraction unit.