Pittman Arm from a 1960 Corvette - but 3714674?

[Tom D.]

A Pittman Arm, 3714674, from my March built 1960 seems original, mainly because of what appears to be a date cast = "1 04 0". (Perhaps it's "104 0" - The space between the 1 and 04 is not quite as big as the space between 4 and 0.)

AIM calls for a number 3733448, which I don't have. A friend has a 1956 Corvette with this "448" arm, but dated(?) with "1 04 2".

My questions:

1. Why would these two both have the number "1 04", if not just by chance?
2. More important: Has anyone else seen a 3714674? On a Corvette?

THANKS!

(Pitman, just in case someone is searching for...)

[Tom D.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

As stated above, I hope for comments on 3714674 (Pittman arm for some Corvettes?)

And, we have now found third one, numbered 3733448. It ALSO has a a code starting with "104". (Notice I am not calling this a cast date this time, because that's three in a row that have "104" followed by a single digit. )

[Joe L.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

As stated above, I hope for comments on 3714674 (Pittman arm for some Corvettes?)

And, we have now found third one, numbered 3733448. It ALSO has a a code starting with "104". (Notice I am not calling this a cast date this time, because that's three in a row that have "104" followed by a single digit. )

Tom------


First of all, keep in mind that the number shown in the AIM is a PART number. The number found on the arm is a FORGING number which may or may not be the same as the part number. It's also possible that more than one forging number was used for the part number. In fact, that's exactly what I expect occurred here.

I can't find any record of the 3714674 number. However, while P&A information provides the identifying forging number for most Chevrolet pitman arms, the 56-62 Corvette arm is the exception. This may imply that multiple forging numbers were used. It does say that the arm is identified by a daub of black or yellow paint. Of course, that's probably long gone on your arm by now.

Also, the SERVICE part number for the 56-62 arm was GM #3733446. I would expect the same part number used in PRODUCTION. Are you sure the part number shown in the AIM is 3733448?

[Bill M.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

AIM calls for a number 3733448, which I don't have. A friend has a 1956 Corvette with this "448" arm, but dated(?) with "1 04 2".

My '59 has a 448 with 1 04 2 also.

[John H.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

My '59 has a 448 with 1 04 2 also.

The 1 04 2 identifies the set of forging dies used to produce that forging; forgings aren't dated.

[Tom D.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

Sorry, look for 3733446. We have since found a fairly original '56 (and another '56 in process) with the other number, which is 3714674 (if I typed it right this time.)

[Tom D.]

Re: Pittman Arm from a 1960 Corvette - but 3714674?

Joe: I agree the 448 number (found on the pittman arm) is the number for the forged arm only. The assembly is "446".