C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

[Oliver S.]

I had my rear shocks replaced 3 years ago and by chance saw later that the washers (can’t see if actually lock washers) are behind the nuts not the head and this is contrary to how it should be - a minor detail but occasionally mentioned. Clearance is no issue in my case - most probably not the original bolts. Is there any other technical reason why this is important?

Oliver

[Alan D.]

Re: C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

Check your AIM (my 64 is at Sec 4 sheet B4.00) shows it behind the head, your AIM may be in different Sec. 63AIM also shows behind head.

[Joe L.]

Re: C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

I had my rear shocks replaced 3 years ago and by chance saw later that the washers (can’t see if actually lock washers) are behind the nuts not the head and this is contrary to how it should be - a minor detail but occasionally mentioned. Clearance is no issue in my case - most probably not the original bolts. Is there any other technical reason why this is important?

Oliver

Oliver-----


Regardless of how typically installed, a lockwasher is equally effective (as minimally effective as they are) in a fastening system whether installed under the bolt head or under the nut. I suspect the reason for under bolt head location in the upper rear shock mount application is to provide for a more easy installation of the nut with the close proximity of the rear compartments.

[Terry M.]

Re: C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

Oliver-----


Regardless of how typically installed, a lockwasher is equally effective (as minimally effective as they are) in a fastening system whether installed under the bolt head or under the nut. I suspect the reason for under bolt head location in the upper rear shock mount application is to provide for a more easy installation of the nut with the close proximity of the rear compartments.

Joe

My guess is that bolt was installed on the chassis line before the body met the chassis. Clearance at St Louis would not have been an issue. Were they thinking of field replacement? I find it hard to believe that, but who knows. That assembly order has always been a mystery to me, but it does add to the fun of what we do.

[Jim D.]

Re: C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

Oliver-----


Regardless of how typically installed, a lockwasher is equally effective (as minimally effective as they are) in a fastening system whether installed under the bolt head or under the nut. I suspect the reason for under bolt head location in the upper rear shock mount application is to provide for a more easy installation of the nut with the close proximity of the rear compartments.

I think that's the reason considering that the original nut is half the thickness of a standard nut.

[Oliver S.]

[Joe L.]

Re: C2 rear shocks - why LOCKWASHER BEHIND THE BOLT HEAD?

Oliver------


The AIM instructed that the orientation of the bolt MUST be with its installation from the outside. It is likely that this instruction was made for subsequent SERVICE purposes because, with the exception described below, there would have been no PRODUCTION reason for such an instruction. So, if your car was originally built with the opposite orientation of the bolt, then there was an error made at St. Louis.

With one possible exception, there would also have been no PRODUCTION reason for the installation of the lockwasher under the head of the bolt. The possible exception would be that the designers wanted to keep the inside fastener assembly as "thin" as possible to avoid possible interference when the body was installed on the frame. After all, I highly doubt this operation was done with such precision interference with the shock mount bolt would not be possible at some point during the installation process. However, I really think that SERVICE accessibility was the primary reason for the lockwasher location and the use of a thin nut in the fastener assembly. In addition, an application-specific bolt was used. This bolt was 2-1/8" in length and had a relatively short thread length. I believe the bolt length was to ensure that there would not be excess bolt length to cause possible PRODUCTION interference or complicate SERVICE accessibility.