1966 differential numbers

[DAVE CUNNINGHAM]

I am wondering about the numbers on my differential housing, I am hoping that it is the original unit. Number are as follows:

Date code cast into the housing- 6 25 5

part # on housing- 369914

stamped into housing- AW W 15 4 E 1

the car is a 1966 450 horse 427 roadster, it was produced in the second week of production, Sept. 1965

The stamped numbers seem to refer to a 68, but why would it be cast so early.

Any help would be appreciated

Thanks,

Dave

[John H.]

Re: 1966 differential numbers

Dave -

I think you'll find that the diff housing casting number is 3899143, which was used from '67-'75; 1966's used 3876476-N. Can't explain why it has a 1968 "AW" ratio code or an end-of-May assembly date.

[Wayne M.]

Also, carrier cast date maybe G_25_5 ? ...

for 25th July 1965. These are sometimes a very poor quality casting, and if the driver side yoke seal doesn't leak, is not protected from corrosion.

But as J.H. mentions, the carrier cast # and the bottom flange stamping don't seem to correspond to early '66 production. Is your rear cover # 3871375 WITHOUT a cast date on the flange by the filler plug ?

You'll have to pull the rear cover to check the rest of the numbers/dates on the ring and drive pinion gears.

[DAVE CUNNINGHAM]

Re: Also, carrier cast date maybe G_25_5 ? ...

thanks Wayne, yes the rear cover does have that part number without a date, I will pull it apart to look at the dates on the gears.

Dave