Steerin' Box Woes

[md21722]

Hi all,

Dealer told me my steerin' box was too TIGHT when I complained about handling a few days after alignment (strangely, car was GREAT until I jacked up the front end to change tires - I since have put the originals back on but handling problems persist). The steering does seem somewhat tight in the center position.

Took it to the mechanic for his opinion today. There is NO free play in the center position, BUT there is a more normal amount with the wheels turned off-center! He says he's never seen it that way before - its the opposite, loose in the middle. He loosened it up one turn to get a little play in the center position and suggested I put another steerin' box in, because if it he loosened it anymore (as he'd like to) there'd be too much play off-center.

Wondering if anybody has any experience with a box too
tight?? Does a box that's tight normally wear the way mine has?

Thanks!

[md21722]

Here's an update. With the loosened steering box, the car drove pretty good in very windy weather - for 100 miles. Then, it started to get squirrely & all play from the box was gone!! Luckily for the rest of the trip the car was not squirrely. Wierd. I'm replacing the "Self Tightening" box this weekend. Anybody see this before?

[ako]

Brian,

My car has the same problem. The steering play is tight (which is what it should be) when wheels are straight. But when the wheels are pointing either left or right, there is excessive steering play. I check this play when the car is stationary.

I wonder if the steering play has something to do with the tires. My front tires are a little worn on the outer edge.

Were you able to find a solution?

Where is the steering box? Steering box hasn't been touched

for 38.6K miles now.

RV
------------------
1992 300 TE Wagon (W124) 113.6K miles

[md21722]

ako,

Mercedes-Benz sets 10 mm play in the steering box at the factory. 25 mm is allowed maximum. If your box was adjusted to less than 10 mm play, then all I have ever heard says it will wear very rapidly, getting uncorrectable loose, at which time you get to buy a new steering box.

I used a replaced steering box from my parts car. It has much smoother motion (the other one was 'gritty' by comparison). When measuring the play, what happens at the far left or far right is not important. Set play at center and check at 20 deg left or right. I suspect mine has more play at 20 deg too, but I haven't recently checked it.

The steering box won't cause your excessive tire wear & changing it does not require an alignment or alignment check according to the service manual. Front toe-in is the very likely cause of outside tire wear.

If you get under your car and look up under the drivers side near the steering linkage you will see a large black box bolted to the frame. This is the steering box. This is near where the drives side footwell is. There is an arm, called a pitman arm that secured the drag link and left tie rod to the steering box. On the other side of the car, there will be the idler arm where the drag link and right tie rod meet at an arm that bolts to your frame. This will be near the exhaust flex pipe or cat.

If you have doubts, I would sugget having the dealer check alignment & steering box play. In my experience they seem to be the best for alignment and can also offer input into problems with the steering box. I have not yet been to an indy that can properly set front toe-in. My main problem was wind sensitivity and this was from front toe-in because of a hidden problem with the right tie rod. Steering boxes are expensive so if that's the problem probably a good idea to find a good used one.

Let us know how it turns out.

[ako]

Brian,

Thanks for the reply. I think for now I'll just leave the steering box alone lest I break it. And you're probably right about my car's toe-in/out problem. My mistake was I just had the wheels aligned by one of those alignment shops. And I don't recall them using a spreader bar for the alignment. So I really doubt that the toe-in/out was set correctly.

Thanks again.

RV

[haasman]

With the use of the spreader bar during an algnment, is it put behind or ahead of the front axel? Or, is it put between the sides of the wheels that have the tie-rod?

What is the amount of pressure needed?

I have always wondered AND at the next alignment I will be sure to 1) Make they use the spreader bar and 2) To have it positioned properly.

BTW, is my understanding correct, that the spreader bar is used during an alignment for MBZs because as the car moves down the road, its suspension has a natural tendancy to out?

Thank you in advance,

Haasman

[ako]

Haasman,

I don't know the answer to any of your questions because I myself only found out through this forum that Mercedes alignment
has to be done with the use of a spreader bar. I do not know how
that is done.

I've been driving different Mercedes for many years and didn't realize that the alignment shops that I was going to weren't doing a good job.

Maybe some of the pros can answer the questions.

Sorry I do not want to make any guesses.

Take care,

RV
----------
1992 300 TE (M103) 113.7K miles

[md21722]

The spreader bar is placed between the front of the front wheels, to "toe them out" if you will. The main purpose is to take the play out of the steering linkage. M.B.DOC says you don't need it if you have new parts. However, that has not been my experience. 55-75 ft-lbs (can't remember which) pressure it put on the bar.

MB spec for front toe (total) with spreader bar is 20 min or 0.33 deg (at least for my '87 W124). The first indy THOUGHT he set it to 0.33 deg, but I knew from symptoms that it was not. A second indy took the same reading. BUT the dealer read it as 8 min, and corrected it to 20 min ~ 0.33 deg. So, in my case, the dealer alignment resulted in a toe-in change of 0.20 deg & the car does better.

Note with the non-dealer alignment my tires were wearing perfectly.

If your tires are wearing on the outside (as all mine were when I purchased the car) then you either have too MUCH toe-in all over the place (which would not cause wind sensitivity & oversteer, but rather the opposite) or you have suspension components worn.

With the dealer alignment my tires still wear perfectly.

[stevebfl]

A while ago I did an article for "Import Car" magazine: http://www.continentalimports.com/ser_ic4232.html . Ihave been aligning MBs for near thirty years and had never used a spreader bar. Because of a thread that took place at the time on this forum, I decided to get a spreader bar and see what difference it made. Much of my results are explained in the article, but basically when placed at the front spreading the leading edges, the cars have had anywhere from .3 to 1.0mm toe difference. The standard range of toe setting is 2-3mm.

The main reason I did this test was to try and find out why I had no problems with tire wear in the thousands of alignments I had done. The answer lies in a number of things. First from a number of tests the use of the bar makes negligible difference in the readings. Second I have always spread the the wheels from both the front and rear manually (I am 6' 4") to evaluate play in the steering linkage. I do not accept play of more than 1-2mm. Also I always load the suspension to see the difference in toe to affect my settings. And lastly I believe that when doing alignments to "do no harm". By this I mean that I use the sum total of driveability (do a road test first), current or past tire wear, and the specs either set by MB or modified by experience to decide on what to set the car.

[md21722]

Steve,

Can you clarify what you mean by "Also I always load the suspension to see the difference in toe to affect my settings."

Maybe this is what's different if the spreader bar is not used? The reason I ask, two indys aligned the car, then one dealer. All three agreed on the rear toe. The two indys agreed on the front toe, but the dealer did not, and added 0.2 deg toe-in.

Looking forward to your reply,

[haasman]

I am confused.

I go to indys and I always get outer tire wear. I go to the dealer and it almost always is correct and long-lasting (no outer tire wear)

What do the dealers do that the indys don't (or don't know)?

This is very helpful.

Haasman