1970 Pitman Arm Correct?

[Allen N.]

I have my steering box, pitman arms and nuts and bolts cleaned up and ready to install. Gary Ramadei did an excellent job restoring my steering box, and I replated the carriage bolts black oxide.

I am concerned about my pitman arm. It does show to be a power steering pitman arm with GM 3741383 part number on it, but all of them I see on ebay have part numbers with a different appearance followed by a letter. Is my pitman arm correct or should I replace it?

Thanks,
Allen

[Edward J.]

Re: 1970 Pitman Arm Correct?

Allen, that part no equates to a p/strg. for your corvette don't worry about the letter after. Joe L will likely see this and can tell what the letter means.

[Joe L.]

Re: 1970 Pitman Arm Correct?

Allen-----

Most, if not all, Corvette power steering pitman arms do have an "A" or "B" suffix after the forging/part number. I do not know, for sure, what these suffix denote. I strongly suspect that they refer to some slight difference in the forgings which does not affect the application or interchangeability of the arm. Whether a certain suffix predominates in any model year I do not know.

The GM #3741383 pitman arm actually predates the first Corvette application. It was first used for 1958 Chevrolet passenger cars and then used on passenger cars through 1964. For the 1958-62 period it was used on all passenger cars; for 1963-64 it was used only on those with power steering. My GUESS is that the arm you have pictured originally resided on 1958-62 passenger car and was probably forged either at some GM forge plant other than Tonawanda (note the lack of the "T" following GM; Tonawanda was usually good at emplacing its "T" forging mark while the GM Detroit and Buffalo forges usually did not) or, perhaps, at an outside forge.

In any event, this arm is 100% perfectly functional for your application and since it does have the correct part number, I don't see how any judge could decide it's incorrect. I definitely do not think this is any sort of reproduction.

[Allen N.]

Re: 1970 Pitman Arm Correct?

Joe,

Thank you very much. Your GUESS is very logical as your responses always are. You are a huge asset to the NCRS, and I always enjoy reading your responses.

Thanks,
Allen

[Gary R.]

Re: 1970 Pitman Arm Correct?

Hi Allen,
I believe the arm you have is the original to that box. I certainly could be wrong in the fact someone swapped it out if changing from Manual to power but I really doubt it. "Typically" the boxes have been overlooked when working on the cars in the past, not a body off but rather when they were used for daily drivers. Engines, Trans, and Diffs were swapped out a lot more.

Here are some pictures from my library. I might as well post them before I lose 3rd party posting. Hope they help.

Comparison of the 2 types, #451 & #383, I always reference the last 3 numbers.

[Joe L.]

Re: 1970 Pitman Arm Correct?

Joe,

Thank you very much. Your GUESS is very logical as your responses always are. You are a huge asset to the NCRS, and I always enjoy reading your responses.

Thanks,
Allen

Allen------


Do you know if this car is an original power steering car or if it's been converted?

[Allen N.]

Re: 1970 Pitman Arm Correct?

Joe,

I got the car through a divorce settlement with no historic data. I do not know if it is an original power steering car or not. I am assuming my pitman arm was actually from an earlier passenger car and have bought a pitman arm from ebay that cannot be questioned whether it is original or not.

Thanks for your help,
Allen