SouthSeaPirate

I've experienced DW before; this isn't like it. Usually it takes impact or some event to set it off, and will wobble till stopped.

At 55mph and thereabouts I have a vibration (wobble in steering, slight shaking in truck), almost like the beginning of DW, but goes in and out at almost perfect pattern if I stay in the 55mph area. 60 it drives fine.

Ideas?

2001 4x4 Manual 4.0

jpz

Interesting, I have the exact same problem. Right at 55-60mph. I'm planning to get under the Jeep soon, and start looking for worn/loose suspension components. I do have one bent front sway bar end link, however I don't expect that to be related.

I'd be curious if anyone else has experienced this and can identify a target area. My jeep is a 2000 Sport, Auto, 4wd with the crappy front and rear Dana axles.

Morat

At that speed I'd bet on rear wheel balance.
(and it's a cheap place to start)

SteveMongr

X2 wheel or tire.

SouthSeaPirate

Rear wheels?
I forgot to mention, when slowing from higher speed I can feel it in the steering wheel.

ehall

These things are really susceptible to tire balance at 55 MPH for some reason, its like a curse

NM-XJ

I've got a 98 that is doing this. My initial concern was that this was the onset of DW, but I can assure you it probably isn't. I have:
1) Balanced and rotated: no change
2) Took off and tested without the newly rebuilt front drive shaft: no change
3) New TREs and steering components from pitman arm to knuckles: no change
4) New track bar: no change

I'm getting new shocks this week, but I don't expect any improvement. I'm convinced it's a wheel/tire issue and it's so minute I don't care to try and fix it. Two Jeep buddies couldn't feel it until they put their hands on the wheel. So to heck with it - if it bugs me I CANT DRIVE 55!!

NM-XJ

Oh, ehall, to follow up on your comment.

I would put money on there being a system harmonic at whatever frequencies correlate to 55-60 mph wheel rotation speed. That's the only reasonable explanation for this speed range causing so many vibration issues for folks.

Would be neat to talk to an original designer and see if it is a known harmonic (for a short time I was a chassis design engineer and 95% of my job was vibration analysis).

Bocefus

Its a tire/wheel problem at that speed for sure. I had the same issue and believe me it is very frustrating. Even with brand new tires, I had the issue. After getting an alignment, 4 new shocks, steering stabilizer, checked the entire suspension, I went back to the tire shop and found 3 of the factory steel wheels had a wobble that was visible when spun on a balancer.

I then decided to find some aluminum Ecco wheels, and ended up having to buy 7 wheels until I had a complete set of 4 that were relatively straight. Even then, I had to place the straightest ones on the front in order to get no vibrations. Bottom line, your wheels need to be straight and tires well balanced or you will get vibrations at 55-60 with these Cherokees. You may want to consider going with new aftermarket wheels for a better chance of getting straight wheels, but I wanted to stay with the stock look.

SteveMongr

A bent or out of true wheel can balance just fine on a machine but will be out of round and cause issues. New cheap steel wheels are notorious for this.
Also, a tire can have a broken belt in the carcass that will cause a wobble or vibration.
And bad hub bearings can cause intermittent vibrations, but usually will growl and become hot. An infra-red temp gun is great for diagnosing wheel bearings.

Bugout4x4

There is an interesting phenomenon that we in the tire industry call "telegraphing". Sometimes a rear tire and wheel assembly can make it feel exactly like it is coming from the front. I have even had folks swear up and down that there is a problem with one of their front tires and it turned out to actually be a tire on the boat trailer they were towing and not the tow vehicle at all. When suspecting Tire issues check them all

Bugout4x4

Best suggestion I have read on this site yet Steve, as a Heavy Truck Tech the Temp Gun is the most important tool I have ever purchased or used in my life. So many issues can be diagnosed, verified or ruled out in two seconds! Anyone that does any work at all on Automotive should own one!

SouthSeaPirate

I might be one of those people that swear up and down it's the front
I can feel it in the steering when braking from above said speed.

I just find it strange that so many people have this problem. I can't imagine all my years and cars, only an XJ would have problems with tires; and Ive had some ****ty tires.

Bugout4x4

I think a lot depends on the difference between solid axles and independent suspension on a fairly light vehicle like these. A solid axle can even enhance a problem in the rear to the front. I remember the days when all tires were still Biased Ply Nylons.


Everytime we got on the highway we had to take it easy and wait for the tires to warm up before the flat spots from sitting overnight would go away. the last tire to quit bumping was more than likely lower on pressure than the rest and even when it was the rear it tugged at the steering wheel on solid axle vehicles.


I was just suggesting a universal rule of thumb that has been overlooked many times.

SouthSeaPirate

So new tires and balance is the best place to start?