Help, Vibration at 55 mph...?

Hello.
I've just recently acquired an 89 Cherokee 4.0L thats in overall geat shape. I have been replacing and reapiring all the little things that need fixed. However, I'm currently experiencing a severe vibration when I take it onto the highway and reach 50-55 mph on up. I've recently put on a set of tires that I know were balanced (from my TJ). So I really don't believe this is it. In addition I've replaced the steering stabilizer (which was leaking) thinking that might've been the cause. It still hasn't gone away. Any ideas or thoughts as to what might be cauing this vibration or what I should check next

Thanks in advance for your help.

Regards,
Gary
89 XJ Laredo

U-joint?

Yucc-man, can u explain this for me? Not sure how/where they are located...one at each front wheel maybe? How would I check it to confirm that it is the U-joint?
Gary

Rear driveshaft, there are two u-joints in the shaft and when they start to go bad there can be vibes; my 89 did it at exactly the same speed when one of my caps spit out a few bearings and went dry. That was years ago, and just about the time I learned about proper u-joint maintenance

my cherokee had real bad shakes at 55 at stock hidth. it felt like death wobble could start at any second. it was unbalanced wheels, bad steering stabalizer, and shot bushings. i also had a frozen u joint in the front driveline that was causing a loud humming and vibe at most speeds. hope that helps

arty:

OMG. That was it. I just realized that my wobble was caused by a U-joint on the rear drive shaft.

I never put two and two together until reading this thread!

I'd HIGHLY SUGGEST that you or your mechanic inspect your xj's u-joints ASAP. My XJ just got a new transmission because of a worn u joint. While it was in the shop I told them to go ahead and replace all the u joints. (175k and 15 years old). No vibration after that! I forgot all about the wobble because I was so happy to have my Jeep back from the shop. Never noticed the wobble had been corrected.

Anyway, my XJ did the same exact thing. At about 53-55 MPH it would start shaking like a tire was out of balance or something.

the same thing is happening to mine.... i guess im gonna have to check it out

Neglected to mention the semi-obvious. If you've lifted the Jeep, expect some vibes, especially if the u-joints are older. The way I've heard it, the get 'worn in' to a certain operating angle and changing that can disrupt things, causing vibe.

Changing the steering stabilizer may be masking other problems with the steering. A properly set up front end really shouldn't need a stabilizer, but that is assuming all components are in excellent shape.

Jim

There is a difference between a "wobble" or "shimmy" and a "vibration." Vibrations don't usually start at 55 MPH.

If this is a wobble or shimmy and it starts at 55 MPH, it is due to wheel balance. Still don't know why, but regardless of tire size an imbalanced tire always starts to shimmy at about 55 MPH, and if you drive through it will smooth out again above about 65 MPH.

Doesn't matter if the tires are new. Most tire shop "techs" don't really know how to use their expensive machines, they're getting minimum wage, and they do a minimum wage quality job.