Steering Gearbox slop?
 

85 300SD - how much slop in the gearbox is too much? Is there a good source for used parts, I noticed that I new one is about $600-$700. Also when I had BigO tires rotate and balance the tires, they noted that there was excessive play in the tie rod ends, I got under it while someone was turning the wheel was not not able to notice any play in the steering linkage at all, only in the box, I tried to tighten down the allen bolt, but did not make a big difference.

Any advise would be helpful, I normally do most of the work on my own vehicles, but have never owned a MB before (just bought it last weekend)and my only other experience with diesels is our Dodge 3500 Cummins.

Thanks

The steering box play adjuster spins clockwise to increase play and counterclockwise to reduce play. If you did not know this, you may have made things worse with your adjustment. I think you're looking for no more than an inch of play at the circumference of the steering wheel. If you go too thin on the play, you'll eat up the innards of the box in no time. It's normal to have more play when the wheels aren't pointed dead ahead.

Check also that the bolts holding the steergin box to the frame are properly tightened. This gets into a sticky area because MB uses encapsulated bolts (bolts with baked on Loktite) that should not be reused.

Sixto
95 S420
87 300SDL

The steering box ought to be the last thing you adjust to take out slack. Usually something in the front end suspension is the casue. My 240D, owned since new, has never had the box adjusted.

Len
'83 240D 343,000 miles

really, i have replaced my box once and all susp. components all around the same time. i notice a great difference with the new box v. the old one.

Thanks for the info, I have not gotten a hold a manual yet, so I appreciate letting me know that their adjustment screw is counterclockwise, All of the vehicles I have adjusted have been the opposite. Is there an indicator to know when you have hit the limit of the adjustment.

Everything else seems tight to me, yet there is a little bit of a warble at interstate speeds, I am going to have alignment checked, as gearbox slop should not stop an alignment from being done. Also tires have been balanced and are newer.

It is difficult when I first purchase a used car, trying to figure out where someone else left off in maintenance and learning the difference between quirks and something being wrong.

So far I love the car and the ingenius engineering that no one else could touch in the mid 80's and today.

Thanks again.

Another MB trick is that when you have an alignment done, don't let them hook the steering wheel to the brake pedal. There's a cap somewhere on the steering box. Remove the cap and fit an appropriate size rod (screwdriver should do) into the hole and engage the slot in the steering shaft. That is the proper straight ahead setting. If the steering wheel is off, reset the steering wheel. Chances are you'll be forever correcting your alignment if you force an alignment without keying off the center position of the steering box.

Basic advice on this is let an MB dealership do the alignment or take it to someone who knows about locking the steering box. "Huh?" is your cue to go somewhere else.

Sixto
95 S420
87 300SDL

Thanks again for the advise, I backed the adjustment bolt on the gear box all the way out and it is about perfect. Then I had it aligned and it runs straight down the road smoothly. Although as an FYI, I talked to the dealer and they stated that in 85 the 300 series did not need to be locked from the gear box, also I was unable to find any type of cap on the gear box, anyway thanks again for the info.