i replaced my gears (8 3/4) from stock to richmond 3.91 a few years back. since then ive had a vibration that comes from the rear. tires are balanced, rims are strait pionion angle good. the vibration starts at 75 mph and gos away at 85 or 90. could a twisted axle cause this or is it the nature of aftermarket gear sets? a friend says his does the same but he drags and dont bother him to much. any help or ideas would be graitful.

 

moe in wichita ks
check the rear and front u-joints. my guess isthey are worn or are not centered.

 

Ijust put a new driveshaft in this winter so ill try looken at the angles again. bad gears or tweeked axles woulnt cause this?