Up until about 4 months ago my truck has developed a steering jerk to the left, and it will come and go. Usually happens when I turn a corner and then on down the road. I've checked, and had someone else check the front end and there is no play in anything. Steering shaft is even good and tight. Is there such thing as a centering valve in the steering gear box? I just replaced the gear box due to a leak and hopefully to solve the problem (which it didn't). I'm really lost now on what to look at next. There's not much left that could be wrong. When it's not doing it the truck drives straight as an arrow down the road.

 

Mine did that and it had a low tire and the pitman arm nut had 1 turn left on it when I found it, but you already replaced the box.

 

Not real sure about the jerk, maybe a broken shackle or something? And yes, there is a return to center located in the gear box.

 

Check your axle ujoints, one could be seizing and causing the jerking feeling.

Just a thought.
Glenn

 

Is the return to center have an adjustment on it. My steering wheel is off about 1/4 of a turn when I'm going straight down the road. I've checked front end tow and it is dead on.

 

I dont think it has an adjustment, if it works correctly you should be able to let go of the wheel when making a turn and it should spin back close to staright. Have you checked all of your front bushings?

 

And a very good thought, too.

 

I had the same problem after I replaced the shaft seal on my steering box. Here is a pic of a box.




Loosen the stamped metal lock nut. Then use a small punch or what ever you have that fits the pin hole in the adjustment block. Tighten the adjustment block 1/8 of a turn clockwise and test drive afterwards. It took 1/4 turn to get the catch out of my box.

 

Mine had a similar problem,and it turned out to be a cracked power steering pump bracket.The bracket was cracked/broken.Ezra.

 

ive had this happen and the caliper would occasionally get stuck and jerk the truck. it was in a blazer though

 

I agree with this. Don't forget, even when you are in 2wd and the front axleshafts aren't turning, that u-joint still needs to flex when you steer. If one cup is seized, it'll do exactly what you describe.

On a W250, there's no way to adjust the steering for steering wheel centering. Make sure your toe is right, inspect for bent parts, make sure BOTH axles are square to the frame, be sure the steering coupler is in good shape and has been assembled correctly, then remove the steering wheel from the column and re-install it straight. There is no master spline for the steering wheel on these trucks.

 

I second RURALCRUISER 007 on the front axle joints . You should be able to turn them both with out binding . You can test them by just locking your hubs only NOT the transfer case and driving down the road . Turn L & R .. Your steering wheel shouldnt jump back and forth like your locked in 4X4 if it does I would think Axle joints .

 

Don't know if there is a difference between the W250 and the D350 Srw (don't know why there would be) but dads steering wheel is 90*off and you can't just pull the steering wheel and turn it because there Is a master spline it will only allow the steering wheel to go on one way. they are both the same year of truck also. The reason his is 90 off is becasuse the steering shaft had play in the orginal, he pulled the steering shaft off a 85 and the mounting was 90 off at the top end. so he has to rebuild the orginal. Just something to look at i guess.

 

Thank You all for the great info. I've done some more diagnosing. With the hubs locked in(transfer case unlocked) the truck drives straight down the road w/o any trouble. Drove that way for about 3 miles. Got out, unlocked the hubs and instantly its got a jerk to the left. Pulled in garage and with hubs unlocked tried spinning both u-joints. I can get about a full turn on each joint, then it wants to spin the drive shaft. Acts like something is binding up in the front axle. Still not making sense but hopefully it will come together. When I replaced my steering gear box I welded the crack in my steering gear bracket, so all it tight there. Thank you.

 

Okay new discovery. It currently looks like my right u-joint is seized up. It will turn one way but froze when trying to turn the other. This may be the answer to all the problems.