70 + mph vibration on 85'
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
70 + mph vibration on 85'
Smooth up to 70 then feels like a bad u-joint but they've all been replaced. It's cyclical in nature, 1 second on, 1 second off. Everything feels tight under the car. Any ideas?
Also would like to change the color of the interior from tan to black. Is this possible without breaking the bank? Thanks.
Also would like to change the color of the interior from tan to black. Is this possible without breaking the bank? Thanks.
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
There are a lot of things it could be. My car would do the same thing above 75 mph, it turned out to be the rotors. When I changed the rotors and brakes the vibration when away. Also, are you sure the wheels are balanced correctly? Have the u joints on the drive shaft been changed?
Jack up the car and see if the rear wheels will move from side to side, if it does, you could need new rear wheel bearings.
Good luck
Randy
Jack up the car and see if the rear wheels will move from side to side, if it does, you could need new rear wheel bearings.
Good luck
Randy
7th Gear
Joined: Nov 2004
Posts: 7
Likes: 0
From: livermore ca
just replaced both rear wheel bearings on my 85 this last weekend do to the same problem & now its smooth as it was 20 yrs ago...check wheel bearings direct on ebay, both rears for under 190.00 shipped...i didnt think it was the bearings, since i had replaced them 10k miles ago, until i put new 18" tires & rims & still had the vibration, did another check & couldnt figure out how i missed the amt of movement i was getting when grab'g the tire top & bottom, so dbl check your bearings...
btw, my car has 78k miles on it & to think i have replaced the rears twice now, tho i did noticed that the torque on the spindle to hub & bearing nut was 81ft lbs per the shop manual i used the 1st time & this new set came with a note in the box to torque them at 180ft lbs which is a big diff, not to mention i had to get another torque wrench that went that high since mine topped out at 150ft lbs.....
btw, my car has 78k miles on it & to think i have replaced the rears twice now, tho i did noticed that the torque on the spindle to hub & bearing nut was 81ft lbs per the shop manual i used the 1st time & this new set came with a note in the box to torque them at 180ft lbs which is a big diff, not to mention i had to get another torque wrench that went that high since mine topped out at 150ft lbs.....
Thread Starter
Burning Brakes
Joined: Jan 2007
Posts: 921
Likes: 0
From: Houston TX
just replaced both rear wheel bearings on my 85 this last weekend do to the same problem & now its smooth as it was 20 yrs ago...check wheel bearings direct on ebay, both rears for under 190.00 shipped...i didnt think it was the bearings, since i had replaced them 10k miles ago, until i put new 18" tires & rims & still had the vibration, did another check & couldnt figure out how i missed the amt of movement i was getting when grab'g the tire top & bottom, so dbl check your bearings...
btw, my car has 78k miles on it & to think i have replaced the rears twice now, tho i did noticed that the torque on the spindle to hub & bearing nut was 81ft lbs per the shop manual i used the 1st time & this new set came with a note in the box to torque them at 180ft lbs which is a big diff, not to mention i had to get another torque wrench that went that high since mine topped out at 150ft lbs.....
btw, my car has 78k miles on it & to think i have replaced the rears twice now, tho i did noticed that the torque on the spindle to hub & bearing nut was 81ft lbs per the shop manual i used the 1st time & this new set came with a note in the box to torque them at 180ft lbs which is a big diff, not to mention i had to get another torque wrench that went that high since mine topped out at 150ft lbs.....
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
A few items to consider as possibilities.
As tires get some age and ware on them, they might not run smoothly at the higher speeds due to belts shifting in the tire, but will balance up great.
Since U joints have been replaced, there is an alignment of the drive shaft and the differential. The relationship of rear end and shaft should stay the same. Although I have not had this problem myself, I am aware of this rule and respect it. If they are out of phase, I don’t know what one might experience with different cars.
As tires get some age and ware on them, they might not run smoothly at the higher speeds due to belts shifting in the tire, but will balance up great.
Since U joints have been replaced, there is an alignment of the drive shaft and the differential. The relationship of rear end and shaft should stay the same. Although I have not had this problem myself, I am aware of this rule and respect it. If they are out of phase, I don’t know what one might experience with different cars.
