I've got a '94 Explorer, about 140,000 miles on it. About 3 weeks ago, it started pulling really hard to the right out of no where (didn't hit a bump or anything, I was moving on flat ground). After a about a day, it stopped, then started about 2 days later, then stopped again for about 2 weeks until it started again.

I took it to the shop, they told me the ball joints are bad. Would bad ball joints cause intermittent pulling like that? I would think it would be a constant pulling that would stop every other day or so.

 

Do you still have the auto hubs? I might look at one side intermittently engaging/disengaging.

 

The drive shaft would have to engage to activate the auto hub, does not get my vote...

Check the radius arm bushings...a bad one would cause the axle to shift back and forth.

 

Did you happen to notice if one wheel was hotter than the others, or have you noticed a burning smell after a drive? Maybe you have a brake at one corner that is dragging and causing the pull. The intermittent symptom is odd for any issues, brakes or suspension.

-Rod

 

No burning smell after driving. The guy at the shop took off the front drive shaft (thought the 4WD might be engaging on one side on its own), to see if it would remedy the problem, however, it continued even after that.

It shouldn't be a stuck caliper, had all of them changed about a year ago.


I think I need to find another mechanic, usual guy insists that the ball joints be taken care of first and has yet to actually check anything else. The ball joints may in fact be bad, but I think that's a separate issue, and I really don't want to change them until I know what's causing this pull... Too much money, when there might be another major issue there.




I'll try to get the radius arm bushings checked out. Any other ideas anyone?

 

If the calipers were changed but not the brake hoses, you could still have a brake issue.

Has the shop tried swapping tires from left to right to see if the pull changes?

Just last week I checked over a co-worker's 2WD Mistu Montero Sport. He had it aligned for a pull, the shop aligned it but it still had a pull. The shop also told him he needed front inner and outer wheel bearings and races. When I got the wheels off the ground I was surprised the shop even aligned it with all the looseness in the bearings. It turns out the bearings were just night tight, the bearings and races were still fine. I tightened them up and check out the other items the shop said needed to be replaced (rear u-joint, carrier bearing) which also checked out fine. The next day he IM'd me to let me know his pull was gone.

So, to make a short story long, if loose wheel bearings could cause a pull, I imagine a loose ball joint could as well. If the ball joints are loose enough to cause a pull, they need to be replaced to keep the vehicle safe to be on the road. Have you witnessed the looseness in the ball joints? You might also want to verify the looseness is due to ball joints rather than wheel bearings as well. Getting that second opinion may not be a bad idea.

-Rod

 

I did have the tired rotated as well, still pulled in the same direction shortly after.