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New motor mounts = new vibration.

3617 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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I'll give that a shot next, I really hate to have to go through that nightmare again but... I plan to completely rebuild the front end so maybe it will be easier to get to the passenger side mount a little easier with the control arms removed.

gtkane said:
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.
I really hope it's not that, I dont really feel like pulling the tranny.. :cry: Is it possible I could have damaged it while jacking up the motor/trans to change the mounts?

davesyo said:
there is a possibility that it could also be a torque converter problem since it seems better in neutral. ,unless maybe it is just a tune up issue or misfire
Im not getting under that heap while it's running.. I'll sit in the van and have someone else get under it.. :twisted:

Bikehauler said:
It's possible but not probable. Unless you have a big dent in the bottom of the pan from jacking I doubt you did any damage. I would suggest you BLOCK the wheels and have some one sit in the van with it in gear and their foot on the brake. Be very careful and listen for the noise. From the outside it should be fairly easy to find the noise.
Please don't run yourself over!! :dunce:
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