asuderma

I have a vibration accompanied by a noise when I let off the gas pedal above 35 mph. I can feel it in the floorboard, and it sounds like its coming from somewhere in the front driver side. I have replaced the front driveaxle U-joint (the front one), and the front driver side U joint, all to no avail. Someone suggested to me the motor mount might be bad and the motor is vibrating on the frame when decelerating. Any ideas?

Thanks in advance.

cherokee51890

i have the same problem im thinking the motor mounts myself. if anyone has any idea or knows exactly it would be greatly appreciated to know what the problem is.

jeepxj99

Does the vibration feel like it is coming from directly under you or more toward the engine compartment?

Also, does it ever vibrate while accelerating or above certain speeds?

Diesel

Checked hub bearings?

asuderma

It never does it when accelerating, but since I heard the noise I haven't gone above 70. It's really hard to tell exactly where it's coming from, but it seems to come from a general forward direction.

asuderma

I just had the hub out to do the U joint, and it seemed fine. No play and spun freely with no grinding or catching.

Diesel

Feel it in the steering wheel or in the seat?

asuderma

Neither. Only in the floor.

Diesel

Possible motor mount, its weird that you only feel it while decelerating and not at idle.

asuderma

That's what I thought, but my reasoning is that its not under any load when idling, other than friction load.

Diesel

No but that is usually when you feel things the most, at lower rpms, and Idle being the lowest I would imagine you would feel it the most. Do me a favor, get under there and try to shake the driveshaft

asuderma

The front driveshaft? Did that, now that the one U-joint is replaced it has no play at all.

Diesel

Rear driveshaft

asuderma

Solid as a rock.

Diesel

are there any cracks, dents, holes, zipties