Steering Arm Plug

[Jim S.]

I believe that power steering was made standard in 1977. Before that time the steering arms had two holes for the tie rods. On power steering cars the hole furthest from the knuckle had a metal plug (i.e. with power steering, the tie rods could only go in the fast steering hole.)

Was the plug installed at St. Louis when they knew that the chassis was to be power steering? Or were there two different steering arms one for manual and one for power?

Jim

[Jim S.]

Re: Steering Arm Plug

Never mind. I found my own answer.

The AIM (UPC 3A, Sheet 3) shows Rivet 3794056 being installed on the steering arm with the N40 (power steering) option. So it was done at St. Louis.
Jim

[Joe L.]

Re: Steering Arm Plug

Never mind. I found my own answer.

The AIM (UPC 3A, Sheet 3) shows Rivet 3794056 being installed on the steering arm with the N40 (power steering) option. So it was done at St. Louis.
Jim

Jim------


Also, some of the arms used in PRODUCTION after power steering became standard only had the holes for the power steering tie rod positions. I think these arms were used from 1978-82. They were never sold in SERVICE, though. All SERVICE arms had 2 holes.

These later arms, GM forging #465071 and 465072, are also MUCH stouter pieces than earlier arms. Later SERVICE arms have these forging numbers but with dual holes. So, for the most part, if one finds a set of these arms with single holes, they were those used in PRODUCTION; a set with dual holes indicates SERVICE arms.

During the 1977+ period until the time that the second hole was eliminated on PRODUCTION arms, I think the rivets may have been installed on the arm at the sub-assembly plant where the front knuckles were assembled. Although the rivet is called out in the AIM's, it is not shown as to part number. So, I think that it was likely not installed at St. Louis in this period.

Also, the rivet is called out in the AIM's right through 1982. However, I believe that its use ended well before 1982. Just when, I don't know. It would be interesting to hear from folks with 1977 to 1982 models . It's very unlikely that the steering arms or rivets, if present, would have been disturbed or changed on these cars.

[Jim S.]

Re: Steering Arm Plug

On minor things like the rivet, I can see that Chevrolet may not have taken the time to change the AIM. Since the rivets themselves would only be part of a BOM (Bill Of Materials) for a Vette with manual steering, when power steering became standard there would never be an order generated to purchase additional rivets.

However, the AIM would have to be changed to reflect the beefier 465071 and 465072 steering arms with different part numbers. At that time it would be just carelessness that failed to eliminate the rivets.

Jim

[Joe L.]

Re: Steering Arm Plug

On minor things like the rivet, I can see that Chevrolet may not have taken the time to change the AIM. Since the rivets themselves would only be part of a BOM (Bill Of Materials) for a Vette with manual steering, when power steering became standard there would never be an order generated to purchase additional rivets.

However, the AIM would have to be changed to reflect the beefier 465071 and 465072 steering arms with different part numbers. At that time it would be just carelessness that failed to eliminate the rivets.

Jim

Jim-----


The steering arms were part of the front knuckle assembly as delivered to St. Louis. So, the steering arms were not shown as separate parts in the AIM. However, the part number for the knuckle assemblies did change during 1977. The new part numbers, GM #467149 and 467150, may reflect the change in the steering arms. Given the number series similarity, I would say it may imply that the new steering arms were part of the new assemblies. The same part numbers for the assemblies were then used through 1982.

It may be, however, that for some period of time the steering arms were actually of the 2 hole variety and with the rivet used as a plug for the unused holes. Then, at some point, they may have decided it was stupid to continue the machining operation necessary to create the unused hole and the cost and effort to install a plug for that unused hole. It's also possible that the part number for the knuckle assemblies did not change when the machining change to the arms occurred.

If we could hear from some folks with 1977-82 Corvettes who could check this out at a glance, it might shed some light on this issue.

[Jim S.]

Re: Steering Arm Plug

Joe,
What it boils down to is: Once vehicle production began, some changes were very critical and therefore were done quickly and well documented with a paperwork trail. Other changes were not so critical and so were down the list. Others (even less critical) may not have been done (or at least documented in a timely manner.) Lastly, some things just got overlooked; and despite the "system" things were getting done or manufactured anyway.
Jim

[Brian M.]

Re: Steering Arm Plug

Here are two good examples.