modifications > CPE Rear Motor Mount

Why did you put the CPE Rear Motor Mount on your RS?

The factory RS rear motor mount is made to minimize NVH (noise, vibration and harshness) from the engine/transmission to the chassis. However, one of the cheapest ways car manufacturers lower the NVH is to use rubber bushings. In this case you have the engine/transmission rear mount so soft with pliable rubber that it hurts performance. If you own a RS try a few spirited starts using launch control. That clunk noise you hear is the rear motor mount bottoming out trying to resist the push back from the engine/transmission.

CPE eliminates the rubber bushing in the lower part of their 2-piece rear motor mount setup by using a machined aluminum piece. The upper piece of the rear motor mount from CPE is aluminum, but it is equipped with a rubber bushing that is stiffer than stock (durometer 65).

Date Completed:



- CPE xFlex Rear Motor Mount Stage 2


- 1/4", 3/8" drive ratchets, a few extensions, sockets (T30, 15mm, 19mm)
- 15mm ratcheting combination wrench
- 10mm hex (allen) wrench for new driver side rear motor mount bolt
- Large flat-head screwdriver to remove wiring harness clip from rear motor mount stud
- 1/2" Torque wrench (80 lb-ft)
- 10,000 lb 2-post lift (optional, but highly recommended!)
*A friend for moral support is always optional.


1. About 1 hour install. I took my time because of taking pictures for this website.
2. Undertray has to come off. :)
3. I recommend doing this swap on a cold engine/exhaust. Otherwise you will get roasted a few times in cramp quarters around the bottom of the engine.
4. Lay everything out as you go (old vs new). CPE instructions are pretty good. CJ Pony Parts website has a video. If it doesn't fit don't force it.
5. No wiring plugs need to be disconnected for this swap. You do have to temporarily remove a wiring harness hold down from the top rear motor mount stud.
6. I used red loctite on all of the rear motor mount bolts when I put them back.
7. I also used a sharpie to mark the rear motor mount bolts to see if they back off.
8. I removed the factory downpipe support bracket from the back of the engine for room to reinstall the rear motor mount stud. I didn't put the downpipe bracket back (not needed).
9. Torque for all rear motor mount fasteners = 80 lb-ft.
10. Reversible back to stock.