Steering not returning to center
 

I have a 1986 300E with an amazingly low 60K miles.
In the last 10K miles, the steering has slowly begun not returning to center. No matter the road, or speed, the car will go where ever the steering is pointing. It is difficult to drive on the interstate as you must constantly pay close attention the wheel to keep it straight.
I have rebuilt the steering box and adjusted it to specs.
Aligned front end.
Changed power steering fluid with MB synthetic fluid.
Replaced filter.
Replaced struts and strut bushings.
Replaced tires.

The power assist works great even at idle and sitting still. Everything feels smooth and easy when up on jacks.

I have been searching these forums and have found no similar problems. I would greatly appreciate any info to lead me in the right direction.
Thanks

Are you sure the pump is pumping?

Could be the shuttle valve in the steering box.

Have you checked the condition of the steering damper - a few years back people used to report this as a problem part (but as with many things this seems to have gone out of fashion at the moment).

Other than that consider the condition of each part of the front suspension and steering - work through it all methodically.

Check your service records for front ball joint replacement.

If you are not sure as to when they were last replaced, I would definitely have them inspected by a reputable MB indy or just have them replaced for peace of mind.

W124 ball joint failure thread: http://www.peachparts.com/shopforum/diesel-discussion/314231-ball-joint-failure-w124.html

Thanks for the help
 

Thank everyone for the help.
Everything up front is like new, clean and tight. This car had been in storage for years as the original owner was aging.
I have had it to two different front end shops familiar with MBs. They can find nothing wrong.
I ordered ball joints yesterday. They feel fine, but one has a cracked boot. They should be in on Monday.
I will update if anything happens.
Again, thanks for the help

Please define "feel fine".

Ball joints can seize up and not have any play but won't swivel. This is most common on the lowers because they see high spring loads and are in a position where a failed boot will collect water. Lift the car, unlock the steering, engine off, grab the tire and steer it. It should feel smooth offering some resistance but not a struggle.

Ask anyone that had a 70's ford truck with seized king pins what it is like to drive, it will be same as yours.

Surprisingly changing my idler arm bushings with an idler arm repair kit cured this issue for me on my W126.

Question
 

Just out of curiosity....who did the alignment and what tires are you rolling?

Hey, looks like I got my answer here, although I'll have to replace them first to be sure if it is my problem too and it's an W124. :)

I recently changed the ball joints on a W124. It too had the spooky steering on the highway - he had it checked by about 8 shops including a benz shop - who all checked it with wheel hanging - the correct way is to compress the spring (jack under control arm) and then lever the joint to check play.

For any odd reason you find the boot is ripped on the ball joint - immediately purchase a new joint, its far cheaper than paying tow, bodywork, upper strut mount and labor.

btw - the ball joints I changed out were really bad, one was sloppy and one was nearly siezed (rusted in place) car was a 2.8 300E.

Just out of curiosity, can you elaborate on spooky steering? My 124 loves to pull to the road crown. I've had it at a number of different shops. Alignment is in spec, even tweaked a bit to try to compensate for the crown. It was great at one point in time but *something* changed and I'm not sure what.

The ball joints and LCA bushings were changed and now have 90K on them. Not sure of brand though.

I see you adjusted the steering box.

I've had the same problem on two MBs, where the "adjustment" went too far, and the box was the source of the resistance.

Back off the adjustment nut slightly and see if the return improves. Otherwise, the ball joints are a good bet....

Jim

spooky steering is constant correction of the wheel as the car rolls down the road - it was almost if it was twitching left and right on its whim.

start with basics, even a loose wheel bearing can cause this.

Bad rear links can cause spooky steering also. But with only 60K I doubt that is the issue here unless some rubber bushing has failed or something.

Rgds,
Chris W.
'95 E300D, 436K

Front wheel bearings are new. Installed and adjusted this past December.
No change.

Front coil springs and pads too. No change.

Summer (Michelin) to snow tires (Genereal), minimal change, maybe a hair less aggressive.

Within the last two weeks one of the arms in my rear end have started squeaking very loudly when I get out of the car. Driver side only. They all were replaced Dec 2013. Meyle brand as they were the only one who had a nice kit.

I suspect its the camber arm. Not sure how much it could or could not be influencing things.

I had an alignment done a few months ago. Then took it to Sears for tire change up. Sears said my back tow was out but they don't align 124s and said I would have to take it elsewhere. I didn't tell the it was dealer aligned the day before.

Seized ball joints act like someone is holding the steering wheel while you are trying to drive. When you steer a little bit you encounter resistance, turn harder, overcome the resistance and overshoot your intended position. And, since the wheels can't self center on their own, you are constantly fighting to keep them on center. ( and overshooting )

I haven't driven a street bike but it would be the same as turning the steering damper all the way up and then some, riding around without leaning just steering.