Mid-Year Rearend Date

[Jim Damasiewicz]

What is an acceptable interval for rearend dates. My car was built around 12/17/65.

[Wayne M.]

Re: Mid-Year Rearend Date

Jim --- Assuming you're referring to the assembly date and ratio code stamping, found on the bottom flange of the case (where it bolts to the rear cover), I'd say 2 to 3 weeks advance on final car assy, more if ratio is one of the less popular, possibly more if your 12/17/65 date is the trim tag code of an A-body car. The case CASTING date could be up to 2+ months prior to assembly. It is doubtful that the rear cover (to which the spring bolts) has a casting date (would be located near the flange next to the filler plug, if it had one). If your rear is a known original, I'd be interested in knowing if your rear cover has a cast part # 3830303 or 3871375 (upside down, at the flange where it bolts to the frame crossmember).

[Kenneth S.]

Re: Mid-Year Rearend Date

My '63 was built April 17th, give or take a day and my rearend is dated April 8th.

[Mark J.]

Re: Mid-Year Rearend Date

Jim,

My '66 was built approximately on April 5. The date stamp on my engine, transmission, and rear end are all May 23.

Mark

[Mark J.]

Re: Brain Fade

That would be MARCH 23, not MAY 23. Sorry.

Mark

[Jim Damasiewicz]

Re: Mid-Year Rearend Date

The code on my rear-end is FB 11/22/65, could this be my original rear-end with my build date around 12/17/65?

[Wayne M.]

Re: Mid-Year Rearend Date

Jim --- No problem with 3+ weeks between your diff and car build; note that Ken posted a 1 week spread. Mark's dates are a little shy of 2 weeks, and I must admit a little brain fade myself; should have said that, for A.O.Smith bodied cars, if referring to build date from the trim tag, the span between diff assembly [or any other S.Louis installed component], can be SHORTER than for an S-body car, even to the extent that the A-body was assembled BEFORE the mechanical components.

[Robert C.]

Re: Mid-Year Rearend Date

Jim, FYI, Rear end differential codes and dates are not judged in the NCRS.To hard to see! But yours is fine for your build date.


Texas Chapter NCRS