Part number read diff C1

[Jerry G.]

I have a 61 FI car that is missing it's "P" case. What part number should be on it. it's an April build car. i know the date code numbers , just don't know the part number on the case . Is it 3725899 or3743833 or ??? Jerry

[Joe L.]

Re: Part number read diff C1

Jerry-----

It should be 3743833.

[Jerry G.]

Re: What is 3788812

I see another differential on ebay which is claimed to be for 61 Corvette with part number 3788812. Is 3743833 the only "correct" posi differential case part number? Jerry

[Joe L.]

Re: What is 3788812

Jerry------

GM casting #3789812 (not 3788812) was used for late 1961 and all 1962 Corvettes with positraction, but I don't know when the changeover occurred. I believe that 3789812 is primarily a 1962 piece.

However, if you were to find a GM #3789812 that was correctly dated for your car, then I'd say that it could very well have been used on your car, regardless of when your car was built.

[wayne loron]

Re: What is 3788812

The latest 3743883 housing I have documented was cast I-27-0, and the earliest 3789812 housing was cast I-7-0. As is the case with all "running changes", there could always be some overlap. So, if the housing cast date is 2-6 weeks prior to your SLAD, you should be fine. Wayne Loron