Rear Shock Mount Failure

[B0omsauce]

Hello,


After a long time of utilizing forum knowledge, I am looking to give back. Note, this may be my only post so I will try to be as complete as possible.
I recently purchased a used 2020 Explorer Limited Hybrid AWD and at 29k miles it developed a rattle/clunk from the rear. The noise sounded like something loose in the rear passenger body panel by the rear wheel well. Upon a very thorough inspection (I stripped the interior to the sheet metal) I determined the noise was coming from the passenger rear suspension. After some trial and error, I determined it was the shock mount. If you look up how a bad rear shock mount sounds this was identical to my symptoms. The PN for the mount is LB5Z-18A161-A. When I compared the old mount to the new it seems there was a material/supplier change as the old had a number of LB5Z-18A161-AC and the new was LB5Z-18A161-AD. I was unable to prove the mount had failed through testing and inspection both on and off the vehicle. What I’ve concluded is that the mounting plate inside the mount ended up grounding out to the body and transmitted the clunking noise. It appeared that the new mount may have used a new type of rubber to better isolate the mounting plate.
Note that you will need some tools you likely don’t already own. I purchased a pass-through socket set for the shock shaft nut and a specialty socket to hold the shock shaft itself. The double D socket I purchased was for GM cars (6.1mm x 8mm) size and I had to widen the opening a hair in order to fit. I also had to grind down the socket width to fit inside the pass-through socket.

All in all, the job is a 30 minute one at most and replacing the mount is 1/3 the cost of a new shock with mount. Good luck!

 

[themishmosh]

At almost 30k miles, a better option wouldbe to get the whole rear shock assembly. It is not much more than the cost of just therear shocks. The cost of just the rear shock mount isn't worth it IMHO if your shocks are worn.

 

[MNgopher]

Similar to the previous poster, just don't be surprised when one of the shocks fails at much lower mileage that you would think. Just went through this on our 2021 XLT with a failing seal on the passenger rear shock at 45,000 miles. Many reports on this page of shocks failing at low mileages.

Cost of the shock with the shock mount was lower than the cost of just the shock, so went that route on replacement. Extremely easy job. (with the right tools of course).

 

[hbalek]

Similar to the previous poster, just don't be surprised when one of the shocks fails at much lower mileage that you would think. Just went through this on our 2021 XLT with a failing seal on the passenger rear shock at 45,000 miles. Many reports on this page of shocks failing at low mileages.

Cost of the shock with the shock mount was lower than the cost of just the shock, so went that route on replacement. Extremely easy job. (with the right tools of course).

Many reports of many major components failing at low mileages. This is just another to add to my list including: fuel pump, cat converter, battery, A clutch, rear window defrost, rear camera twice, both front CV boots and axles, FADA, half-shaft speed sensor, driver seat panel and all window switch chrome tips. I'm currently at 50K miles but most of these occurred in the first 2 years/25K miles. Luckily all occurred during the 3/36 and/or powertrain warrranty and were covered free of charge.

 

[MNgopher]

Many reports of many major components failing at low mileages. This is just another to add to my list including: fuel pump, cat converter, battery, A clutch, rear window defrost, rear camera twice, both front CV boots and axles, FADA, half-shaft speed sensor, driver seat panel and all window switch chrome tips. I'm currently at 50K miles but most of these occurred in the first 2 years/25K miles. Luckily all occurred during the 3/36 and/or powertrain warrranty and were covered free of charge.

And a contrasting experience. At 46k miles and 3 years, the rear shocks are the only "real" issue we've had.

 

[hbalek]

And a contrasting experience. At 46k miles and 3 years, the rear shocks are the only "real" issue we've had.

The 2020's were known for more problems than the later model years. Mine was built in November 2019.

 

[hbalek]

And a contrasting experience. At 46k miles and 3 years, the rear shocks are the only "real" issue we've had.

Lucky you! This is still my favorite of my 5 Ford products owned: Ford Tempo, Mercury Mystique and 2 Lincoln MKZs. But it's also my least favorite due to all of the warranty repairs and inconveniences.