Bad Highway Vibes

[ExNews4XJ]

I searched but my problem is specific an really starting get on my nerves. Ok heres the deal I just put a dana 44 in the back of my 98 with new 4.56 gears a lock rite, new diff bearings, and wheel bearings. I also just rebuilt the transfer-case with all new bearings and a tera sye. also brand new rear drive shaft. i don't feel play in either yoke or in the slip yoke of the drive shaft. i currenlty don't have a front drive shaft so thats no the problem. Vibes start and get real bad right at about 75mph and seem to get better if i go up over 85. i'm at 6in of lift and shimed so the pinion angle is also good. vibe sounds real fast so its not a tire/wheel. Any sugestions. cause i'm lost and sorry for the long post just need help before i get mad and do something stupid, like sell the heep.

[xjj33p3r]

Check the u-joints for any wear.

[00Classic]

If ujoints are OK I would still check wheels and tires. If you are running aftermarket wheels that are not hubcentric or you don't have hub rings it will make a vibe, steel wheels will create less problems. Tire balance can do some unusal things also if you have out of balance and excessive road force. Which with the tires most of us run road force is always bad.

[ExNews4XJ]

My wheels are factory jeep wheels from a 88 pioneer they are the 10 spoke alluminum. and are hubcenric. tires are 33x10.50 BFG All-terrains ballenced but i will have discount do it again. All my u-joints are new and tight. also the vibes start like flipping a switch right at 70mph and if I let off they are gone so its only under power when they are there. strange but they seem much better sometimes then they are really bad others. Also the diff yoke is a new u-bolt one as well.