Driveline vibe and noise
10-20-2016, 04:43 PM
#1
Junior Member
Thread Starter
Driveline vibe and noise
My 2001 cherokee, with no lift lift vibrates horribly when accelerating on the highway 65 mph and over. I also get a rumble/clunk when I let off the gas and get back on it at that speed. If I just keep my foot lightly on the gas the noise will stay until I press more or let go.
So far Ive had the rear driveshaft u-joints replaced with spicers and the shaft balanced. The front driveshaft is out. Tranny and motor mounts are new. I also have an issue with my rims being slightly bent causing a vibe at 55. The rims are being replaced in the next few days but I dont think they are the problem since the main vibe is during acceleration.
Any ideas on what to do next? Its getting to where I don't want to drive on the highway anymore.
So far Ive had the rear driveshaft u-joints replaced with spicers and the shaft balanced. The front driveshaft is out. Tranny and motor mounts are new. I also have an issue with my rims being slightly bent causing a vibe at 55. The rims are being replaced in the next few days but I dont think they are the problem since the main vibe is during acceleration.
Any ideas on what to do next? Its getting to where I don't want to drive on the highway anymore.
10-21-2016, 08:10 PM
#2
Seasoned Member
You had the vibe problem back in March and fixed it with
a Mopar tranny mount. After that, did it run real smooth
over 65?
The vibes you have now, did they come on gradually or was
there a sudden deterioration (like when the rims bent)?
Have you rotated the tires to see if that changes the vibes any?
You probably checked most of these things that come to mind,
but it is worth it to ask yourself :
Are the new motor and tranny mounts all tightened up?
Is there any play in the rear pinion yoke/bearings? Any leak at
the pinion seal? Is the pinion nut tight? Is the rear diff full?
(I had a D35 pinion bearing shatter once while driving to the
mechanic's shop to get it fixed)
Are the U-joint straps still bolted down tight? (I've had them
come loose before twice, and each time the driveshaft fell
down) Any play in the new rear driveshaft u-joints?
Did you grease the slip joint when you put the rear driveshaft
back on?
Are the tranny and transfer case both full of fluid and in good
condition?
I once had a clunk in the rear that that turned out to be the
passenger side front leaf spring mount had come loose from
the frame. Had it welded back on.
a Mopar tranny mount. After that, did it run real smooth
over 65?
The vibes you have now, did they come on gradually or was
there a sudden deterioration (like when the rims bent)?
Have you rotated the tires to see if that changes the vibes any?
You probably checked most of these things that come to mind,
but it is worth it to ask yourself :
Are the new motor and tranny mounts all tightened up?
Is there any play in the rear pinion yoke/bearings? Any leak at
the pinion seal? Is the pinion nut tight? Is the rear diff full?
(I had a D35 pinion bearing shatter once while driving to the
mechanic's shop to get it fixed)
Are the U-joint straps still bolted down tight? (I've had them
come loose before twice, and each time the driveshaft fell
down) Any play in the new rear driveshaft u-joints?
Did you grease the slip joint when you put the rear driveshaft
back on?
Are the tranny and transfer case both full of fluid and in good
condition?
I once had a clunk in the rear that that turned out to be the
passenger side front leaf spring mount had come loose from
the frame. Had it welded back on.
10-21-2016, 09:24 PM
#3
Junior Member
Thread Starter
This is a separate issue from the old vibe that occurred when the vehicle wasn't moving.
I just got it back from firestone who swapped rims for me. This seems to have helped with some of the vibration but I'll have to drive it a bit more to be sure. The noise is still there when backing off the gas. I had checked the rear not long ago and there was no play nor any issues with metal in the fluid. Slip yoke was greased. T-case and tranny shift fine. Ill poke around more underneath over the weekend.
I just got it back from firestone who swapped rims for me. This seems to have helped with some of the vibration but I'll have to drive it a bit more to be sure. The noise is still there when backing off the gas. I had checked the rear not long ago and there was no play nor any issues with metal in the fluid. Slip yoke was greased. T-case and tranny shift fine. Ill poke around more underneath over the weekend.
10-22-2016, 10:05 AM
#4
Seasoned Member
Glad the vibrations are gone. As for the noise when coasting,
you might consider this from the Factory Service Manual:
BEARING NOISE
The axle shaft, differential and pinion gear bearings
can all produce noise when worn or damaged.
Bearing noise can be either a whining, or a growling
sound.
Pinion gear bearings have a constant–pitch noise.
This noise changes only with vehicle speed. Pinion
bearing noise will be higher because it rotates at a
faster rate. Drive the vehicle and load the differential.
If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually produce
a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differential
bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
you might consider this from the Factory Service Manual:
BEARING NOISE
The axle shaft, differential and pinion gear bearings
can all produce noise when worn or damaged.
Bearing noise can be either a whining, or a growling
sound.
Pinion gear bearings have a constant–pitch noise.
This noise changes only with vehicle speed. Pinion
bearing noise will be higher because it rotates at a
faster rate. Drive the vehicle and load the differential.
If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually produce
a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differential
bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
06-26-2017, 07:50 PM
#6
Junior Member
Thread Starter
I figured out that the new rear springs had the back of the truck sitting too high and thus caused the same vibration you would get with a lifted truck. I experimented with weighing down the rear and sure enough that did the trick. Now the springs have finally settled and the vibrations are all but gone. I'm so glad I didn't let a shop start poking around with the tranny/driveline.