checking motor mounts on RWD vehicle

JHZR2

Staff member
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46,303
Location
New Jersey
Hi, What's the best way to check motor mounts on a RWD/4WD vehicle? Since Ive been driving my truck more recently, Ive noticed that just off idle, I get a vibration/shake in something, which I do not feel but hear. I was in a parking garage today where sounds resonate well, and it was very noticable. I got the noise (metallic clunk/vibrate type noise) each time I gave some throttle. The truck is a 98 and they have never been changed. Id imagine it may be a consideration as everything else operates and looks like new. Thanks!
 
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6,990
Location
Everett, Washington
Try putting in FWD with the parking brake on firmly. Maybe a block under the wheel for safety. Watch the engine while someone power brakes the car. Try it in reverse as well. You should be able to tell if the movement is excessive...... By putting it in both gears it torques on each mount in a manner that should expose the weak mount if that's indeed the problem.
 
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19,479
Location
Chicago Area
Right. Some movement is normal. A lot of free movement is not . So simply brake torque in forward and revers with a heavy foot on the brake. Rev it up and the results are immediately obvious.
 
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8,576
Location
Ohio
Sometimes a rattle can be from the exhaust too. I think the best bet is to get under the vehicle and inspect the mounts and exhaust. Usually with a close inspection the problem becomes evident, if an engine mount rubber is torn for example. Sometimes some prying, pushing and banging on the assembly helps locate the source of the problem..
 
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2,053
Location
Detroit, MI
Originally Posted By: JHZR2
Hi, What's the best way to check motor mounts on a RWD/4WD vehicle? Since Ive been driving my truck more recently, Ive noticed that just off idle, I get a vibration/shake in something, which I do not feel but hear. I was in a parking garage today where sounds resonate well, and it was very noticable. I got the noise (metallic clunk/vibrate type noise) each time I gave some throttle. The truck is a 98 and they have never been changed. Id imagine it may be a consideration as everything else operates and looks like new. Thanks!
Kind of vehicle is it?
 
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24,232
Location
CA
I would first start by visually inspecting all of the mounts for any excessive cracking or leaks. My experience with bad mounts is that the rubber inserts will show excessive cracking.
 
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19,686
Location
Sunny Florida
Typical newer mounts are filled with colored liquid that shows easily where the damage is. But most mounts have safety ears and such so very little movement will occur if they do fracture or split. So they can be tricky to tell. A friend broke his drivers side mount on a Charger SRT8 and all it felt like was a loose bottle rolling around in the back seat. It was VERY difficult to diagnose until we actually looked at it.
 
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35,818
Location
NY
I look at the mounts first, make sure the rubber isn't oil soaked and deteriorated as a result of exposure to the elements or a leak. Then as mentioned above, I chock the wheels have an assistant hold the brake and give it gas while in D, then R. Look for a lot of movement, in some cases the engine will rise, then bang down when the gas is released quickly.
 
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