hello all. on my 86 auto coupe. all new u-joints...propeller shaft balanced checked... new wheel bearings front and rear...new outer tie rod ends in front...new tires...new wheels... new trans tail shaft bushing and seal...new spline on drive shaft that goes into trans...the problem is a vibration at 70mph and above...no matter what gear I'm in...3rd or overdrive..vibration is at 2000rpm in overdrive(70mph)...and at 2500rpm in 3rd(70mph)... bought the car about 3 years ago...after full interior rebuild, finally got it out on the highway about 2 years ago and noticed the vibration...2 years later and all the above mentioned parts..still vibrates...starting to piss me off.. PS...Nitrous does not affect the vibration...still exactly 70mph whether on juice or not!!! Smooth as glass at any MPH until you get to 70mph.

Hard To Believe Its Not A Tire Or A U Jt. Aaaaaaaahhhhhhhhh Drive 69---just Funning

Are you feeling it in the steering wheel...in the seats /floorboard or through the whole car? Does it go away above 70 mph ?

whole car..including steering wheel. keep in mind its not a violent vib....some people might even live with it...but I can't.....doesn't go away above 70mph...