I installed aftermarket strut mounts 40K miles ago as preventative maintenance. I have read about how the yellow-foam aftermarket units are prone to failure, but no one could explain why, so I purchased aftermarket mounts for $50 apiece and tried them out.

Recently, I have heard a high-pitched knocking noise (I would almost describe it as a ping) from the right side of the car when going over either small bumps at fast speed or large bumps at slow speed. It didn't sound like sway bar bushings, so I tore the front suspension apart to investigate.

As you can see below, the steel cup that holds the bump stop has snapped off its (very poor) pinch welds and was being popped into the top of the strut mount upon large compressions, causing the pinging noise I could hear from the cabin. It's easy enough to pull these assemblies apart and weld them back together. The aftermarket unit seems to have held up well otherwise.

 

I bought a set on amazon and both failed within 20,000 miles or about 2 years

 

Replaced the upper shock mounts 7 years and almost 50k miles ago with genuine JLR mounts, and they're still healthy.

 

The aftermarket units have only 4 pinch welds where the OEM units have 8, much better penetrating pinch welds. The foam is also different, and I suspect, of a higher durometer. For the labor involved, OES really is the best way to go for these.

 

Not that this comes up often, but for when it comes up for a non-welder, I wonder if a reasonable slathering of JB Weld might do. I'm often impressed with how different JB Weld products perform, and I could see it maybe used in this sort of thing too.

 

Just a reminder, and thanks to Jaaag-driver, for posting the photos, and the use of locking pins. A compressed spring has enough energy to rip off body parts, and then come back again for a second go. If you are not sure what you are doing, leave this to a Pro.

wombat

 

Yep, we have all seen the videos of spring top-hats being sent across a workshop at the speed of sound. Treat this process with the same care that you would perform eye surgery. The spring compressors I use are the "OEM" brand, they're cast iron and I regularly oil the threads and washers to prevent binding and threadwear.

 

IIRC last time I dug into my front shock assemblies to replace the upper control arms, I didn't need to compress the spring. Instead I just let the front hub hang low with suspension fully extended, then loosened the control arms which let the spring be fully unloaded.
I did take care to mark the spring coil position, so that I reinstalled it in the same position it was in originally, not sure it mattered in this case, but in case it did.
The first time I looked into replacing the upper shock mounts years ago, I did try to go the route of using a strut tool to compress the spring, and it was a PITA.

 

To clarify what I believe you are saying- I did not compress the spring to remove the shock/strut assembly from the vehicle. You definitely need to compress the spring to disassemble the shock/strut assemblies into the individual components of spring, shock, and top hat/strut mount. The strut mount is under enormous spring tension, even when the suspension is unloaded. Loosening nut that holds the top hat to the strut, without the spring compressed or with incorrect technique, could have deadly consequences.

I only compressed the spring so I could take apart the shock/strut assembly to access the strut mount.