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Identifying bad motor mount

12K views 11 replies 4 participants last post by  16cherokeeLatwhite  
#1 ·
Hey all,

Anyone with experience replacing motor mounts, looks like I've got a busted one, but not sure if this is rear or passenger side. With the play that I get, I assume rear, but open to suggestions. Here's a video of my KL:


I have a repair manual for this, but honestly contemplating just buying both and doing the rear first, the passenger (or returning if the rear fixes the issue).
 
#3 · (Edited)
Hey Max,

To figure which one...

1. REAR: To tell if it's the rear mount put the car on ramps where you can get under it. Then using your hands, try moving the motor front to back. If the mount is bad, you'll see the rear mount move back and forward. (the mount it located on the top side of the subframe underneath the car connected to a bracket at the back of the transmission. The mount but it has a rubber isolator on it and shouldn't move.)

1. PASSENGER: For either the passenger or driver's motor mount you can use the rock 'back & forward' test however a more reliable test is to look underneath the motor mount for signs of brownish streaks. The mounts are filled with a hydraulic fluid to absorb vibrations and covered with rubber end caps. When the mount breaks the fluid comes out and leaks down the car. For example, on the driver's side, if a mount breaks, the fluid lands right on the end face of the transmission that's visible if you peel back the driver's wheel liner. If you ever see brown fluid leaks on that face, it's the driver's mount that's failed. With the passenger side look directly under the mount section that has the black rubber on it. Do you see fluid running down? (may be dried if it happened a while ago) If so, the mount needs to be replaced.

I put three videos below which cover the procedure on all of them.

Note, the rear and driver's side mounts attach to the transmission so are the same on both engines. The passenger mount is a different part for the 2.4 and 3.2 engines but the changing process is broadly the same.
  • Video #1 is replacement of the passenger side mount in a 3.2 engine
  • Video #2 is replacement of all of the mounts in a 2.4 engine (zoom to about 2/3rds the way through to see how he does the rear mount. The ratchet strap process could also help determine if that mount is bad if you can't visually tell.)
  • Video #3 is the tip to greatly reduce the amount of time and disassembly if you ever have to do the driver's mount. It involves a drill/Dremel for a small plastic modification on the battery tray that takes 10 minutes but will save a half hour of needless disassembly.
Hope this helps, good luck!


1.

2.

3.
 
#4 ·
Hey Max,

To figure which one...

1. REAR: To tell if it's the rear mount put the car on ramps where you can get under it. Then using your hands, try moving the motor front to back. If the mount is bad, you'll see the rear mount move back and forward. (the mount it located on the top side of the subframe underneath the car connected to a bracket at the back of the transmission. The mount but it has a rubber isolator on it and shouldn't move.)

1. PASSENGER: For either the passenger or driver's motor mount you can use the rock 'back & forward' test however a more reliable test is to look underneath the motor mount for signs of brownish streaks. The mounts are filled with a hydraulic fluid to absorb vibrations and covered with rubber end caps. When the mount breaks the fluid comes out and leaks down the car. For example, on the driver's side, if a mount breaks, the fluid lands right on the end face of the transmission that's visible if you peel back the driver's wheel liner. If you ever see brown fluid leaks on that face, it's the driver's mount that's failed. With the passenger side look directly under the mount section that has the black rubber on it. Do you see fluid running down? (may be dried if it happened a while ago) If so, the mount needs to be replaced.

I put three videos below which cover the procedure on all of them.

Note, the rear and driver's side mounts attach to the transmission so are the same on both engines. The passenger mount is a different part for the 2.4 and 3.2 engines but the changing process is broadly the same.
  • Video #1 is replacement of the passenger side mount in a 3.2 engine
  • Video #2 is replacement of all of the mounts in a 2.4 engine (zoom to about 2/3rds the way through to see how he does the rear mount. The ratchet strap process could also help determine if that mount is bad if you can't visually tell.)
  • Video #3 is the tip to greatly reduce the amount of time and disassembly if you ever have to do the driver's mount. It involves a drill/Dremel for a small plastic modification on the battery tray that takes 10 minutes but will save a half hour of needless disassembly.
Hope this helps, good luck!
Thanks for the tips! I’ll have it in a shop tomorrow and will look for the hydraulic leaks / stains.
 
#5 ·
Alright, I'll update this with some info:

All three were bad, but the worst was the rear. Just like in #2, the center part of the rear nearly popped out. It took me a little over 3 hours to replace all three with a lift. The biggest hang-up was the rear, as aligning the hole for the mount and transmission was tough. She now drives just like she did when I got her.
 
#8 ·
Welcome to the Forum @16cherokeeLatwhite ,

Could be a worn half-shaft CV-joint on either the right or left side. See #1 & 2 in the chart below. The way to diagnose is having someone walk along side your car when you go in to a slow, tight turn and see if it's coming from the right or left side. (or find a spot to drive where there's a solid wall where the sound bounces back at you then drive with the wall on the left and then on the right)

Since the motor mounts previously were broken, it's possible the engine/transmission positioning was shifting during the turn so the CV-joints in the half-shaft never got to their full extension of travel. Now that the mounts are replaced, the engine/transmission is staying in one position and the CV joints are flexing further exposing a worn joint.

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