'54 Vette steering pitman arm

[Charles C.]

On the 6 cylinder '53-'54 Vettes, does the pitman arm (that is attached to the steering box) bottom out/engage (hit) the motor mount welded to the frame when the steering wheel is turn fully to the left? This is what is happening on my '54 and I am wondering if this is correct?

Many Thanks.
Charles

[Joe L.]

Re: '54 Vette steering pitman arm

On the 6 cylinder '53-'54 Vettes, does the pitman arm (that is attached to the steering box) bottom out/engage (hit) the motor mount welded to the frame when the steering wheel is turn fully to the left? This is what is happening on my '54 and I am wondering if this is correct?

Many Thanks.
Charles

Charles------


I know very little about early C1 Corvettes. However, it would not seem like it would have been designed that way. Anyway, it might be a good idea to check if you have the correct pitman arm and it's easily checked. It should have the number 3706066 forged on it. This piece is unique to 1953-55 Corvettes with 6 cylinder engine.

[Brett H.]

Re: '54 Vette steering pitman arm

Yes, it's normal for the 53-54 pitman arm to touch the lower engine mount when turning all the way to the left. In later years, (55-56 I believe?) there was a wedge shaped pitman arm stop engineered to the chassis.

[Charles C.]

Re: '54 Vette steering pitman arm

Thanks for both inputs.

I do have the straight arm for the 6 cylinder. Mine has the casting no. 3706028 GM 1 (and has 1040 cast perpendicular to this number).

Joe, could you tell me where your found an indication that the casting no. was 3706066? I guess my arm could be for another GM vehicle. Thanks.

[Joe L.]

Re: '54 Vette steering pitman arm

Thanks for both inputs.

I do have the straight arm for the 6 cylinder. Mine has the casting no. 3706028 GM 1 (and has 1040 cast perpendicular to this number).

Joe, could you tell me where your found an indication that the casting no. was 3706066? I guess my arm could be for another GM vehicle. Thanks.

Charles------


It looks like Brett has confirmed that the arm does contact the mount when turned all the way left. So, I'd say you have no problem. I guess the engineering in these early days of the C1 was somewhat "crude".

As far as the forging number goes, the 3706066 is the forging number for the 53-55 6 cylinder pitman arm as specified in early editions of the P&A catalogs. I can find no reference, at all, to a 3706028. Are you sure you've got the last 2 digits right?

[David G.]

Re: '54 Vette steering pitman arm

I am in the process of rebuilding the steering box on a 54, so I checked the # cast into the pitman arm and I have the same # 3706028.
Is this just a forging # or is this the part #?
Dave

[Brett H.]

Re: '54 Vette steering pitman arm

I am in the process of rebuilding the steering box on a 54, so I checked the # cast into the pitman arm and I have the same # 3706028.
Is this just a forging # or is this the part #?
Dave

Looks like the part number due to the same sequencing as other parts on the car.

[Joe L.]

Re: '54 Vette steering pitman arm

I am in the process of rebuilding the steering box on a 54, so I checked the # cast into the pitman arm and I have the same # 3706028.
Is this just a forging # or is this the part #?
Dave

Dave------


I can't find any record of GM #3706028. The P&A catalogs specify that the forging number for the piece was supposed to be 3706066 and the part number for the finished piece is the same number.

Obviously, the 3706028 existed if you both have that number on the arm. It must have been an alternate forging number.

[Gary C.]

Re: '54 Vette steering pitman arm

Charles, Brett, Dave and Joe,

Charles and Dave - inspect the "8" and you'll find it's a "closed" 3.

'54 P&A Group # 6.179 shows forge # 3706023

Gary
....

[Joe L.]

Re: '54 Vette steering pitman arm

Charles, Brett, Dave and Joe,

Charles and Dave - inspect the "8" and you'll find it's a "closed" 3.

'54 P&A Group # 6.179 shows forge # 3706023

Gary
....

Gary et al----

Are we talking about the PITMAN ARM here or are we talking about the IDLER/THIRD ARM?

The 53-55 6 cylinder PITMAN ARM is supposed to be forged 3706066. The IDLER/THIRD ARM is different. It should be forged 3706023

[David G.]

Re: '54 Vette steering pitman arm

I just reinspected my Pitman arm and the number that is cast into it is definitely 3706028. I also looked at it with a magnifying glass and it is very clearly an 8 on the end of the number (not a 3)

Regards, Dave

[Gary C.]

Re: '54 Vette steering pitman arm

Joe, etal. My bad. Long road trip to/from the NM Regional. Sorry about that. '54 P&A Group # 6.859 shows forged # 3706066 and same part #. Unfortunately, am not able to find a reference to the # 3706028 in my P&A's.
Joe - did you have any luck with 3706028?

Gary
....

[Joe L.]

Re: '54 Vette steering pitman arm

Joe, etal. My bad. Long road trip to/from the NM Regional. Sorry about that. '54 P&A Group # 6.859 shows forged # 3706066 and same part #. Unfortunately, am not able to find a reference to the # 3706028 in my P&A's.
Joe - did you have any luck with 3706028?

Gary
....

Gary------


I can find no reference, at all, to GM #3706028, either as a finished part number, forging number, or identification number.

[Charles C.]

Re: '54 Vette steering pitman arm

Thanks for all the input.

I have looked very closely at the number on my pitman arm (not the third arm) and it is clearly "3706028 GM 1" (the 8 is not a closed 3 but a perfect 8). The measurement from the axis of the opening for the steering box shaft and the center axis of the ball is right at 7". This arm looks exactly like the arm shown in a very old NCRS article by John Amgwert about the differences between the '54 and '55 V-8 arms.

This hobby is great, but challenging.

Charles

[Joe L.]

Re: '54 Vette steering pitman arm

Thanks for all the input.

I have looked very closely at the number on my pitman arm (not the third arm) and it is clearly "3706028 GM 1" (the 8 is not a closed 3 but a perfect 8). The measurement from the axis of the opening for the steering box shaft and the center axis of the ball is right at 7". This arm looks exactly like the arm shown in a very old NCRS article by John Amgwert about the differences between the '54 and '55 V-8 arms.

This hobby is great, but challenging.

Charles

Charles-----


Yes, it's especially challenging when one gets into the "dark ages" of very early C1 cars. The last one of these cars was built more than 55 years ago, not very many were ever produced, and a lot of references source for them have gone by the wayside.

It must be that the 3706028 pitman arm was either a predecessor to the 3706066 or an alternate for the 3706066. The strange part is that the numbers are so close together. That implies that they were released very close to one another and possibly even simultaneously. So, a supercession from the 3706028 to the 3706066 does not seem likely.