Vibration at 60 MPH

[wtucker]

96 Explorer sport, RWD, 2WD, 5 speed 272K miles. Have a constant vibration around 60 MPH, also occurs when I disengage the transmission and coast at 60 MPH. Doesn't do it when I rev the engine up in park to around 2500 RPM. Tires are balanced, rotors have been replaced recently. Clutch, slave cylinder replaced about 40K miles ago. haven't had the drive shaft checked yet, it feels like its more in the front half of the vehilce than the back. Any ideas where to check next?

 

[masospaghetti]

Is the vibration speed dependent (60 mph) or RPM dependent (2500 RPM), or a combination or the two?

Do you get the vibration when revving the engine in neutral?

The way you described the problem would indicate something very unusual. Most vibrations are either speed dependent, RPM dependent, but not both. High speed vibrations could be a wheel bearing, bent rim, bad tire, u-joint, or rear-end bearings.

 

[wtucker]

no, its not dependent on 2500, that was just a check I did at that RPM in neutral while parked. it starts around 60 MPH and lessens around 70 MPH. No vibrations in neutral while reving the engine. Front wheel bearings have ben replaced recently. U joints are original and probaly should be replaced, no damage to rims.

 

[pjtoledo]

try 60 in 5th, and 60 in 4th, maybe 3rd too.
is the vibration the same?
60-70,is kind of a resonant frequency for wheels, any imperfections will be amplified at those speeds.
with that many miles you need U-joints.

Perry