vibration on highway!!

[adham]

i have been experiencing severe vibration on the highway
it starts at about 68mph
it is really rough
what coud it be?

[Ed Blown Vert]

Front Wheels out of balance?

[adham]

i thought that and got them balanced again, but it didnt help

[Ed Blown Vert]

Steeering wheel move when that happens?

[adham]

yes, moves and vibrates

[Ed Blown Vert]

Are you sure they balanced them? Those symptoms are unbalanced tires.

[RAT454]

jack up the ass end and get both rear tires well up off the ground. put it on stands and run it up slowly and carefully to 70. see if you still have the vibration. if not then rotate one tire from front to back and do it again, then the other and see if it just one tire/wheel causing the problem...

this should rule out a tire/wheel problem...

If you don't find the vibration using the above, then you may have a spindle/rotor/brake problem up front. also if it stays on the back even after rotating tires then you may have a drive line problem ( u-joints, axle bearing etc.)

greg

[rbob93]

Could be a ply separation in the tire.

[adham]

the tires are only 5 months old
i did have a brake job done, new rotors, pads and calipers
i think it still vibrated even before that

[adham]

Are you sure they balanced them? Those symptoms are unbalanced tires.

i had 2 different places do them and still no change

[shady milkman]

bent rim? that was the problem with my grand am gt

[b.lee]

torque converter bolts?
where it bolts to the flexplate?

does it viberate while parked, in neutral or park, when you rev it up?

[alkaydenz-28]

i used to have that strong vibration on my dash and steering wheel everytime pretty much when i speed up about 60MPH on my 95 tbird, i had my transmission oil changed, it went away and never came back.

[b.lee]

hrmmmm.

[SSpdDmon]

If it's MPH dependent, it's something in the drivetrain (driveshaft out of balance, tires out of balance, etc.). If it were something to do with the powertrain, it would be rpm dependent (torque converter, flexplate, etc.). I'd check the driveshaft for marks of contact and also check the trans mount if the tires have been ruled out. If that's not it, I'd have the rear end looked at incase you somehow slightly bent an axle or something.

[adham]

thanks for everyone's input
i will take the suggestions into consideration

[MikeSomething]

Wheel alignment is usually what does it to me.

[Soldier1]

Hey, check your torque arm bushing

[b.lee]

any updates on what the problem was adham?

[adham]

not yet, i'm in college now, but i'll be going back home soon to find out