Years ago, I installed a set of Koni Sport shocks. Now, on an unrelated project which had the car largely torn apart, I find myself reassembling the front suspension, and I'm replacing rusty and worn parts wherever possible. In particular, that includes a fresh new pair of shock mounts.

To be clear, I'm talking about these:

(I also replaced the inner shock mount isolators, but had no issues there.)

On the driver side shock, the mount came right off the shock. But on the passenger side, it won't. The nut is off, but the mount seems to be stuck to the shaft. It looks pretty rusty, so I'm assuming that's how and why it's stuck.

I've seen a handful of threads about this, but it was always in the context of replacing shocks, so the advice was always "just throw that whole thing in the trash and buy a new shock mount to go with your new shocks." Well, I can't do that; I'm not replacing my shocks. I need to separate these two pieces, and I cannot damage the shock itself in the process.

Right now I have it held upright, with a pool of PB Blaster sitting in the top of the shock mount, hopefully making some headway. I've done a good bit of hammering against the top of the shock, hoping to dislodge it from the mount -- but despite its worn state, the mount's rubber is doing a pretty great job of absorbing those hits. (My primary motivation for replacing the mount is to replace the rusty shock tower bolts.)

This evening after work, I plan to get out my air hammer and see if that can break anything loose. I'm a little wary of this, because I definitely don't want to mushroom the top stem of the shock too much. Does anyone have a good way to protect it from this? I guess I could thread a nut on and then put a deep socket (too small for the nut) over the top, but I'm all ears for better ideas if you have them.

Does anyone have any other ideas I could use to get these two pieces apart?

 

This worked perfectly. I used a 10mm deep socket. The threads were in poor shape afterward, although I don’t know if that’s from hammering against the nut or if it’s just rust. Anyway, I ran an M10x1.25 tap down and up the shaft a few times and cleaned it all up. There are some threads that are a little shorter than they ought to be, but they’re not where the nut sits when installed — just a section it has to pass through during installation.

I lubed the shaft with some anti-seize, so hopefully this goes a little more smoothly the next time these need to come apart!