highway vibration

M

marcom

Member
#1
#1
i have a 2001 v6, and i've had a rear end vibration as soon as i go past 65mph. this has been going on for a couple years now and i thought it was a wheel/tire out of balance condition. I just got new wheels, which takes that out of the equation. I still have the rear end vibration.

today i hoisted the back end off the ground and removed both rear wheels, put it in gear and took it to 65 again, and i've got the same vibration. Same thing with the wheels back on.

Could someone tell me which components could be causing my rear end to shake like this at highway speeds?

thanks

Marco
 
M

marcom

Member
#3
#3
the axles seem to be true to the naked eye but im no expert. My main suspects are the driveshaft being out of balance, but im convinced its the wheel bearings that are worn out and causing freeplay...I removed the brake assembly and i could push the spindle in and out and move it a little side to side. Are these signs of bearing failure, and if so could this be the cause of the vibration?
 
9

97modgt

Well-Known Member
#4
#4
marcom said:
the axles seem to be true to the naked eye but im no expert. My main suspects are the driveshaft being out of balance, but im convinced its the wheel bearings that are worn out and causing freeplay...I removed the brake assembly and i could push the spindle in and out and move it a little side to side. Are these signs of bearing failure, and if so could this be the cause of the vibration?
Click to expand...
You will get a little in/out play. That is just due to the axles having a slight spacing from your securing pin in the rearend. There should be no side to side play with new bearing but with 100 miles or so, it will be very slight. If it is a good amount of play then I would check them. If the bearings really start to break down then you will end up with filings and in a very short time, the bearing will wear a groove in the axle. If the axle has any slight groove then replace. They will just wear out the new bearings. I don't believe this would cause vibration in your car but checking the axles sence you noticed play will never hurt. I burned up a set of axles and never had a bit of vibration.
 
9

97modgt

Well-Known Member
#6
#6
marcom said:
could abusive driving(dumping clutch, burnouts, etc.) warp the axles? im sure warped axles would cause huge vibration
Click to expand...
I don't really think the axles would warp unless you are putting down lots of power with slicks on but anything is possible. You should have your driveshafted checked. That may be the quickest part to rule out. I don't want you to chase the problem but sometimes starting with the simple things is the way to go.
 
SSChris NY.

SSChris NY.

Member Plus
#7
#7
Has your drive shaft ever been off the Car? U may need to rotate it at the U joint 180 degrees clock wise and drive the Car, it has 8 possible positions, mark were the original position of drive shaft was with a paint pen, if 180 degrees don't work for U and U still have a vibration, move the flange to the next possible setting and drive the car again, by doing the so your dialing in your drive shaft, someone may have changed it original position after doing trans, a clutch or anything related to your drive train, hope this help U out, if you have anymore questions please feel free to ask Me
 
M

marcom

Member
#8
#8
the driveshaft has never been removed. I've heard of driveshafts being unbalanced...if that were the case my car would have had the vibration since new, unless the unbalance condition somehow developed over time.

i want to have it checked for unbalanced driveshaft and bent axle shafts/axle tubes.

i forgot to mention that i've stored the car every winter (six months at a time), but did not jack the car up. The weight of the car was on the same spot since i did not move the car at all during storage. Is it possible this has caused damage to the bearings/axles?
 
9

97modgt

Well-Known Member
#9
#9
marcom said:
the driveshaft has never been removed. I've heard of driveshafts being unbalanced...if that were the case my car would have had the vibration since new, unless the unbalance condition somehow developed over time.

i want to have it checked for unbalanced driveshaft and bent axle shafts/axle tubes.

i forgot to mention that i've stored the car every winter (six months at a time), but did not jack the car up. The weight of the car was on the same spot since i did not move the car at all during storage. Is it possible this has caused damage to the bearings/axles?
Click to expand...
That will not bother the axles. my has has sat numerus times for 7 to 8 months at a time. They are built to hold the weight.
 
SSChris NY.

SSChris NY.

Member Plus
#10
#10
marcom said:
the driveshaft has never been removed. I've heard of driveshafts being unbalanced...if that were the case my car would have had the vibration since new, unless the unbalance condition somehow developed over time.

i want to have it checked for unbalanced driveshaft and bent axle shafts/axle tubes.

i forgot to mention that i've stored the car every winter (six months at a time), but did not jack the car up. The weight of the car was on the same spot since i did not move the car at all during storage. Is it possible this has caused damage to the bearings/axles?
Click to expand...
As a starting point have your Universal jopints checked, if there ok then have your drive shaft checked
 
1red87

1red87

Well-Known Member
#11
#11
Look at the shaft and see if any of the balance weights have broken or fell off. You should be able to see marks where they were spot welded. also check ring and pinion gears. If there are any pits or small chips that can cause a vibration.

marcom said:
the driveshaft has never been removed. I've heard of driveshafts being unbalanced...if that were the case my car would have had the vibration since new, unless the unbalance condition somehow developed over time.

i want to have it checked for unbalanced driveshaft and bent axle shafts/axle tubes.

i forgot to mention that i've stored the car every winter (six months at a time), but did not jack the car up. The weight of the car was on the same spot since i did not move the car at all during storage. Is it possible this has caused damage to the bearings/axles?
Click to expand...
 
M

marcom

Member
#12
#12
i checked the driveshaft. The weights seem to be all there. I jacked the rear end up again, ran it to 70mph and watched the driveshaft as it turned. I found a vibration at the front end where it meets the tranny output shaft. The tranny is also leaking fluid from the top for some reason. I checked for up and down freeplay at the output shaft, there is a little bit. I checked for freeplay of the driveshaft with the handbrake on and 1st gear in, and it has 1/8th turn of freeplay. Is this normal?
 
You must log in or register to reply here.