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New motor mounts = new vibration.

3616 Views 6 Replies 4 Participants Last post by  Heckler
So im trying to isolate a drive line vibration so after reading many many posts in the old threads I figure I will start with the less expensive things to try to get to the bottom of my vibration issue. Well I installed new motor and trans mounts last weekend and now I have ANOTHER vibration when at idle in gear like when I pull up to a stop sign. When at a stop sign in gear when the rpm's drop to an idle the vibration starts, kinda like a rumble that was not there before. If I put it in park or netural is lessens a lot it mainly when in gear. My other vibration issue is at highway speeds.

Do the motor mounts need to break in or something? Could I have installed them incorrectly? Do they possibly need adjustment?
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They don't have to be "broken in", but as far as adjustment, they may be slightly twisted and causing a vibration. Try this:loosen the mount to frame bolts and the through bolt slightly. Idle the engine for a minute,then re-tighten the bolts. That should let the mounts fall into their natural position. Do the same for the trans mount.
You could also try spraying some penetrating fluid on the rubber exhaust hangars in case they have shifted position.
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