Jerky steering wheel issue.

[96XJPete]

I'm looking at purchasing a 99 XJ but took it for a test drive and noticed the steering wheel shakes a bit when turning. It doesn't do it while the car is stopped and you can't feel it at high speeds either. The vehicle has new tires but I'm guessing there is no relation. It only occurs at slower speeds and while turning. I checked the 4WD and that is definitely not engaged, so what could it be? Any ideas would be appreciated.

Thanks

[sector95]

Don't be too quick to dismiss the tires. Let's just say I've had the same problem on both my XJ and my '98 GMC Sierra; my XJ with relatively new and my GMC with new tires.

In the manufacturing process, tires can sometimes have heavy spots in them or they may not be perfectly round. Now your local tire shop can spin balance any tire so that it rotates true.... without any load on it and without any regard for "roundness". Slap the tire on a vehicle and put it under load
and we have a different situation; the tire will behave or feel as if it is out of balance. If that tire happens to be on the front of the vehicle, then the symptoms can manifest themselves as a shaking or somewhat jerky feeling in the steering when turining from straight ahead....this is what happened on my truck and my XJ. If you combine an out of round tire with a rim that is not perfectly round (not too uncommon) and the tire/rim are mated such that they exaggerate each other, then the situation gets worse. Tire shops have two methods to address these situations: road indexing and road force balancing. The first method determines the roundness (or lack of) the tire and the rim as seperate components. The tire and rim are marked or "indexed" and the tire is remounted to the rim in such a way that the high spot on the tire corresponds to the low point on the rim. In the second method, the tire is spun under load (simulating the tire on the vehicle in road contact). Any internal heavy spots will show up and the tire is balanced to compensate for them. Sometimes one method cures the problem and sometimes both are needed. And sometimes the tire is too far out of round for it to be indexed to the rim....

Hope this helps......

mike

[96XJPete]

Mike,

Thanks for the info. It sounds like a definite possibility, but the jerky steering wheel while turning is the only symptom. The vehicle rides perfectly fine otherwise; both at normal and high speeds. There is no other vibration at all. If the tire did have a heavy spot, wouldn't you expect that I would feel it at other times while driving as well? Perhaps at high speeds?

[Ray H]

Possibly axle u-joints.
Lift the front end off the ground with the key in the run position (but not running) and push and pull the front tires as they would do if turning left and right. It wont be easy to make them turn. Once they are turned fully, give them a spin. This will put the u-joints through there full range of motion. They should go through the motion smoothly without any catching, roughness, squeaking or gravely sounds. Do this on both sides in both directions

[AlohaBra]

On a real tight turn, it may be normal because the Jeep has a straight alxle front end. Otherwise the toe-in is off. There is such a thing call toe-out on turns that is controlled by the toe-in setting. That is because when you turn, the outer wheel runs on a larger radius than the inner wheel. Wear on tie rod ends can also cause this.