Thread: Unusual Problem Involving Shocks

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Recently, my truck began making a lound banging noise as I went over speed bumps. I pulled over and investigated to find that a shock absorber had ripped its mounting bolt through the frame rail. Has anybody ever heard of this happening before?



The shock also bent itself up pretty good:



I made a patch out of 3/16ths inch plate:



Welded it in:



And the finished repair:



There was some radial outward cracking in the frame rail after the weld, as expected when welding in such small patches. I found 3 none more than 3/4 of an inch long. I stop drilled them and welded them in.

Yeah.......quite common on a 30 year old truck.

Looks good to me,I'd use larger washers and spread the load over a larger area. Hank

A few thoughts...make sure the shock isn't topping or bottoming out, and check clearances, the tire or wheel might be hitting it at some point in the suspension travel. Also, how stiff is the valving in the shocks you're using? Could be too much for the mounts.
I've had to put outer braces on those stud mounts before, just sticking out into the big wide world isn't the strongest mounting method. Even my IHC Eagle tandem rips 'em out!

Not uncommon on 73-87 truck chassis. Our shop used to do repairs for the nearby Chevrolet dealer and we had to do this more than once.

Used to see that a lot on trucks that were used heavily in rough or off road situations. Found out that the garage department was putting stiffer shocks on the trucks to keep the complaints down, and then the frames were giving out.

Originally Posted by Bob Parmenter

Not uncommon on 73-87 truck chassis. Our shop used to do repairs for the nearby Chevrolet dealer and we had to do this more than once.

How would the repair be done?I never like the idea of just welding a small piece of metal to fill the hole.I have filled the hole and also used a larger backer piece.

I would have liked to patch in a larger piece. You are almost guaranteed to get cracks welding in a small insert like that. I had 3 small cracks but was able to stop drill and weld them. The trouble is, the shock mount is raised from the rest of the frame and it would be a very difficult shape to replicate. So, I replaced only the flat part. Installing a backer would also be difficult because the threads on the mounting stud would be too short and I would have had to pull the engine to do it.

Originally Posted by BigTruckDriver

How would the repair be done?

It depended on which way the break went, but pretty much the way 76 did his. As he said, you have to keep the "pooch" out and can't easily get to the back side.