Opinions needed on W124 Steering Box - PeachParts Mercedes-Benz Forum

92-2.6 · #1 01-22-2013, 04:41 PM

I have a '94 E320 wagon that I've been working on resurrecting for the past two years. It had a burned wiring harness behind the dash which was a huge pain to replace, but the condition of the body and interior made the purchase in that state worth the risk.

The car has had sloppy steering since I've had it running. I replaced both outer tie rods and have replaced the idler bushing assembly as well, but there is still slop in the steering.

I took the car to a trusted indie mechanic who said the steering box is the source of the problem. He recommends replacement with an MB rebuilt unit as his experience with "rebuilt" boxes from other sources has been poor.

In looking through the archives it appears there is some adjustment possible in the steering box on these cars, but the threads I found were not very helpful with really no one reporting back what success this adjustment had in fixing the problem on their cars. If this seems to correct most of the issues folks have with this problem I'm willing to take a stab at this first before cashing in my retirement for a new steering box.

The other question is if anyone can recommend a good source for rebuilt boxes outside of the MB ones given that the cost is about three times what I paid for the car.

Zulfiqar · #2 01-22-2013, 05:04 PM

before you opt for a new box - ask the mechanic to test the friction of the box, your mechanic would have a beam style in lb torque wrench which is needed to test. This can be improvised with a fish scale to read 0.7 or 0.8 lb when pulling at the edge of the steering wheel of the later W124 with pitman disconnected

With the car raised on a lift - the pitman arm is disconnected from the shaft, at this point the steering should be dead straight ahead, remove the airbag and mount a 10mm allen socket and adapter to the steering bolt - attempt to turn the wheel, it should be less 100 ncm - which is about 7 lb/ft of force - if its less than this there is a nut and captive allen grub screw on the box, it is adjusted counter clockwise to tighten the slop - only adjust in 1/4 turns and test.

If you cannot eliminate the slop and are exceeding the friction values then your box is shot, There is a independant firm called C&M Hydraulics that remakes MB steering boxes in Nevada - they are very good in their work.

before all of the above - it is assumed that the rag joint has been tested and the freeplay you are describing is actually "dead freewheel type free play" - what MB describes as freeplay is the actual play in the box which is not limp like a freewheel for 10 degrees movement situation.

The freeplay is sometimes also caused by the steering not being centred in the straight ahead position. These boxes have a bullet shaped spring loaded piston type part that eliminates free play when the wheel is straight.

RPM55 · #3 01-23-2013, 11:06 AM

+1 to what Zulfiqar suggests.

JamesDean · #4 01-23-2013, 12:12 PM

I had my 201 box replaced a few months ago. Well worth the investment. Much better feeling in the steering. I was unable to go with C&M as I could not locate a distributor with a 201 box from them so I was stuck with Maval. I am happy so far with the box.

97 SL320 · #5 01-23-2013, 06:52 PM

There is a web site " 124performance dot com" ( or something like that ) . Dig around there for some steering box rebuild info.

92-2.6 · #6 04-18-2013, 12:59 PM

I thought it would be good to post a follow-up since so often folks don't.

Thanks very much for the suggestion on the C&M rebuilt box Zulfigar. I was able to get one for my car at a very reasonable price through Pelican Parts, and it solved the problems I was having. My mechanic said the rebuilt box was fine which was not his experience with a 500SL that he tried to source a rebuild for a few months back. I don't know who that particular supplier was.

With the new box, alignment, new front struts, and a new set of tires it drives fantastic.

I still have a few jobs on the front end that will need to be taken care of soon. Prior to taking the car into the shop I thought it would be good to repack the front wheel bearings. I found that my front rotors are badly worn, and the bearings are going to need replacement as they both show coloration in the metal rollers.

Fortunately the shop just said to bring it by after that work is done and they'll adjust the alignment for me if needed. No charge.

Thanks for everyone's input. The car is a joy to drive now.

Zulfiqar · #7 04-18-2013, 01:42 PM

with a correct adjusted box on a w124 the steering feel is very different than any other car and is a real pleasure to drive.

The alignment specs for your car are a bit different due to height differences and drag link angle difference. You also might want to ask your mechanic of the ball point position - its the plane of the pitman and idler arm being the same. A new box can change it if the pitman arm is not at the old location on the sector shaft.

http://www.w124-zone.com/downloads/MB%20CD/W124/w124CD2/Program/Chassis/40-0001.pdf

This page tells you the specs, please bear in mind these are in whole degrees not decimal degrees. meaning 0°30' = 0.5°

the wheel bearings may become gray or brown after a few years in use, if they are not heat colored and roll smooth then a repack with fresh grease is all that is required. They are very low cost items too. You can choose to fill the alien green MB wheel bearing grease or buy a generic disc brake WB grease pot.