Motor Vibrations

[Wahugg]

This has gotten technical enough to warrant it's own thread.

I ran a rough trail fairly hard and afterwords the motor vibrated excessively all the time. Park, neutral, and all the gears. A good reference for the vibration is that it is similar to the vibration present when the vehicle experiences a 4x4 bind up. Also present was a clunk in the floorboards upon initial exceleration.

Fast forward 200 miles. The vibration is all but gone except during startup and shutdown. It is much more severe now, but only for the few seconds in startup/shutdown process. It is not noticeable in any gear with or without the brakes depressed. Also the initial clunk is gone.

Dad believes that my engine may be on it's last legs. He believes that this may be a compounded symptom of my cold engine nock. The severe vibration may be the bearing play presenting itself when there is no oil or oil pressure to fill in the gap (startup/startdown).

I personally think this might be the motor mounts but the fact that the symptoms have changed makes me weary of this being the root. Wouldn't motor mounts only get worse?

Anyone have any ideas?

I appreciate it
-Wahugg

[v7guy]

motor mounts are pretty specific, swapping from park to drive makes a noticeable difference as does the rpm. A rock in the transmission mount can cause some pretty significant vibrations from my understanding.


beyond that I can't say your description is specific enough for me to make a guess.

[ErikSS]

I would think with our liquid filled motor mounts that once bad they wouldn't get much worse. They shouldn't get any better either.

[Wahugg]

Apologies, I should have updated this.

The vibrations disappeared over the course of 3 days. The whole situation is truly bizarre. The only situation I can think of is that a rock or tree limb wedged itself between the motor/transmission and the frame/body causing vibrations. Then after driving it around enough the rock/stick wore down or shifted so that it only made contact upon startup and shutdown. Finally the rock/stick worked itself free and now the issue is gone.

That's the best explanation I've been able to come up with

-Wahugg