VTEK1

Okay 99 XJ heavyduty leafs (roughly 2 inch budget lift.) stock front end. 4.0, 125,000 miles. I replaced the u-joints in the front, the wheel bearing on the front passenger side (driverside this wkend) and then I did the leafs about a week or 2 ago. Thought that would get rid of my vibrations on the highway but it's weird. When I start driving the jeep it's fine, then around 30 I feel like the area right under the seat is starting to vibrate. Like the driveshaft is outta whack. The pinion angle is pretty much 0 degrees I'm thinking about putting the shims in to really make it dead 0 but I want to figure out why it's still got vibrations. Another thing is I think one of the rims might be a little bent but not a lot. Would just a little bend in the rim create the vibrations I'm feeling on the highway?? How can you check if the driveshaft is bent, if you even can.

Abovetimberline

The only way I can think of to check a drive shaft is to put a straight edge on it,as far as the rim goes if it is out of balance because of the dent it will cause the vibration,have it checked,I do not think 2" of lift is going to cause any problems.

VTEK1

i know 2 inches isn't going to cause really anything. if anything it's helped the way the Jeep rides on the roads here in Maine and the highway. The driveshaft is outta the jy, and I don't want to replace it since I got to take care of the manifold to pass inspection in MA

VTEK1

anyone else got some more ideas (bump)

4.3L XJ

Checking a drive shaft to see if it is straight is easily done. Just jack up the vehicle and place the rear axle on jack stands so that the wheels don't touch the ground. Start the jeep and put it in gear and let the engine idle in drive or 4th gear if a standard tranny. Then look under the jeep and if the drive shaft wobbles, it is bent.

The other thing you need to do is purchase a angle finder, about $20 bucks at a tool store. Use it to check the angle of the transfer case and the angle of the pinion. They need to be within 4 degrees, the less the better. If they are too far apart, you r drive shaft will vibrate. You can use those shims to bring your measurements into specs.