A strange steering issue just developed in my 1990 W250. Its hard to describe but, While turning slightly to the right, the steering wheel becomes non-responsive for a second or two, and then suddenly jerks to the right to catch up to where it should be.
In other words:
Im turning the steering wheel 30 degrees to the right, but the wheels are still straight for a few seconds....then they suddenly jump to the right.
Power steering seems ok, and there is no noise or binding or anything, just this "slipping".
Almost feels a broken gear tooth in the steering box or something.
Any ideas?

 

If you have checked all the obvious steering and suspension components, it could be a front axle u-joint binding.

 

APD,
Check out the thread titled "weeble wobble". I'd check those front axle u-joints first, had I done that I would have saved myself a lot of time and money not throwing parts at it.

 

Make sure the frame isn't cracked where the box bolts on.

 

Im gonna have to go with the front u-joints. I put a steering gear on mine before i figured out what it was.

 

Is there a way to tell if the U-joints are bad without taking them out?

 

Try and tighten the box adjustment up. Also have someone turn your steering wheel while you watch your shaft for play.

 

ditto on the axle ujoints, my other truck did pretty much the same thing, turned out to be a seized u joint in the front axle

 

X umpteen on the front axle joints. Mine did the same thing & i threw a bunch at it, including a Flaming River steering shaft. It drove GREAT post new axle joint, though.......

 

U-joints also replace steering box still did it and took to frontend shop and found out it was a tight u-joint and now it steers perfectly

 

I would start with the steering shaft and see if the rag joint and universals are intact. If that is ok I would next check the torque on the Pitman arm where it bolts to the bottom shaft of the steering gear box. If the pitman arm is tight check the play in the gear box. Some or all of it can be adjusted out but if it is overtightened it will cause handling problems. Check the frame for damage where the steering gear box is mounted. This is a common problem area. Next come the tie rod ends. You don't want play in those. If all is well check the spring shackle bushings and king pins or ball joints, which ever applies.

 

APD,
you don't have to pull anything to check them out. Get the front tires off the ground supporting your truck on jack stands. Unlock the steering column, lock the hubs, rotate the tire to line up the u-joint vertically with the steering knuckle/ball joints, grab hold of the tire and try to turn it (steering, not rotation), rotate the tire 90 degrees and try steering again testing the other leg of the u-joint cross. The other side could interfere unless you remove the tie-rod from one knuckle. Look at it, think about it and it will make sense. If I had a picture it would help.

Frozen up and stiff front axle u-joints will cause all kinds of wacky and scary steering problems. It's been a few years but it's coming back to me, like suddenly wanting to pull left at 70mph and have to pull hard on the wheel to the right to stay in my lane and then just going away like nothing happened. Also, getting off the freeway and not wanting to turn right for a split second then snapping loose and turning. Both sides on my truck needed replacing. It's a fun job, you'll enjoy it!

 

You guys were right, it was the passenger side u-joint. I jacked it up and turned the wheels to the right, and the passenger side wouldnt spin, but it would spin when pointed straight.
I removed the u-joint and I couldn't it was totally siezed up.
thanks for all the replies!

 

The exact same thing happened to mine too. Took forever to find then easy to fix.

 

DITTO. thats sounds like what mine did a few thousand miles back the bracket for the steering gear cracked