Car wanders on freeway, what to replace???
 

My car has gotten to the point where it drifts quite a bit on the freeway, especially if I am hit by a crosswind. :o I am assuming I should replace my tie rods (all of them) since they are likely 100k+ in age at least. On the parts site I noticed that there are "tie rod ends" and "tie rod assemblies" with a significant difference in cost. Which one should I buy? On diesel giant's pictorial I saw he used the entire new tie rod... all three for my car would be $180. I'll be having the dealer replace them because I don't want to work on steering components.

Any tips or advice on this potential project? I am getting sick of my car wandering all over the freeway, its getting hard to keep it in a straight line! :eek:

Alignment could be out. Check the thrust angle on the back wheels. Mine was well out, and effectively steering from the back.

Also check for play in the pitman and idler arms. Especially the latter.

Why make that assumption?

Maybe the ball joints are shot?

Maybe the guide rod bushings are weak?

Maybe the steering dampener is shot?

Maybe the steering box has too much play?

Making an assumption, as you have done, without going through the suspension carefully by someone who knows suspensions, is just tossing money out the window..........IMHO, of course.

and rear sway bar links

tom w

Has been replaced:

Rear Sway Links
Idler Arms
Steering Damper
Alignment was done less than a year ago (last february)


When you get the steering to a certain spot or if there is no wind outside, it will track straight just fine, its when its more windy, then it swerves around.

The only place I have around here that could check the suspension out is the dealer....and they charge $95 an hour to look at it. :eek: I'd rather be paying that and getting things replaced than paying it for potentially nothing, then having to pay again for the actual repair....

I think my guide rods/bushings are pretty shot as well, but the ball joints look ok, no clunking, and when I grab a wheel and shake it doesn't move/have play.

Potential culprits: Tie rods, steering box, guide rods, maaaaybe the alignment

What would be my best bet for why the car wanders/swerves, especially in windy situations, it feels like the steering wheel is merely a "suggestion" for where the car is going..:eek:

If there is no play in the wheels when you shake them, I would probably rule out tie-rods...

Subframe bushings?

How about cross winds? Remember the bigger the vehicle, the more surface for wind to push on. Winds 30 mph and up do cause us to feel the buffeting.

If nothing is loose suspension wise, it just the physics of driving in the wind. Ever seen an 18 wheeler blown over by the wind?

I would not worry about it IMHO. Even our Jetta get knocked around by a strong cross wind.

easy way to check tierods is to have someone turn the wheel back and forth while the car is up on ramps, and look at each end for play as the wheel is turned. DO NOT TURN WHEEL LOCK TO LOCK WHILE ON RAMPS, the creep can push the car off them. just about 1/4 turn of the steering wheel back and fourth should be plenty to find the problem.
pay attention to the ball joints, the idler arms the steering box, and pretty much every component that is connected to the wheels. look them over one at a time
John

Hmm.. you'd pay them to tell you nothing's worn out and then have the replace things anyway?

Bushings will cause wandering problems. If you know they're bad, replace them first and see where you get to.

The worn out parts are my bet :) You can plink in the dark and replace pieces until you stumble across it, or have someone look at it and narrow the list down. You may even find multiple pieces that need replacing and are cheaper to do all at once.

My 300D's in the same state, and now worse after sliding off the asphalt the other day. If I can't figure out what is wrong, it's going to someone who can tell me. I'll then decide what I can do and what to have someone do.

Many threads suggest it is the sub frame bushings(search: cross wind drifting). I have this same problem and have replaced a bad tie rod, and idler arm kit. I also have one ball joint that is bad, so I'm dealing with the problem until I can replace the ball joint and subframe mounts, which are a pain in the a$$. I am also going to replace the front and rear differential mounts. No point in doing an alignment until everythings' done.

A good way to tell if you have a bad ball joint is to back off a 4"+ curb with the wheel turned so that each wheel comes off seperately. If the ball joint is bad, it will most likely make a loose 'clunking' noise.

So the entire front end is pretty original? At 250k everything is probably a little worn and sloppy. I wouldn't bother having the dealer change the tire rods and drag link. That is so easy! Take the money you were going to spend on labor and do the upper control arms. Start replacing stuff a little at a time.

i would take it to an ordinary alignment shop with benz experience. ask for an alignment. if there are loose parts they will tell you what needs changing for free in my experience. then you can change parts yourself or have them do it. you may be able to supply the parts too in which case you can probably save about half on the parts.

i wouldnt ignore it. a benz is very stable in the wind.

good luck.

tom w

Man, that could be a number of things. Subframe bushings, ball joints, lower control arm bushings, track rod mounts, and the list goes on.... I've been tracking down a steering vibration and replaced all the rubber in the rear and almost everything up front, vibration is still there. The w126 has pretty complicated suspension.

I had the same issue. Wandering at highway speeds, especially in a wind. I just replaced all of the busings, ball joints (upper and lower) and complete tie rods (the old ones were so corroded I doubt that they would have loosened up enough for an adjustment). I cannot believe the difference it made. my '85 300d now tracks straight and true, and there is no longer a vibration in the steering wheel. I did all of the work myself, except for the alignment, and it was fairly easy. I had 340K on the original supsension components. It was the best $250.00 I have spent on the Benz. FYI.

hatteras is prolly right at that mileage it is all worn and I agree with Walganuth too a GOOD shop for alignment will spell it all out for you My 126 hugs the road in all conditions but I have the reciepts to prove it

I've been thinking about the subframe bushings...the kit for replacing them is $128....are they difficult to do yourself? isn't it...risky undoing those huge bolts that hold up the subframe? :eek: :confused: I don't want to do my tie rods myself because I live a good distance away from the dealer and by the time I got there for an alignment by brand new Michelin's would probably be destroyed, and I got the deal of the century on them, so I want to keep them preserved.

Are the upper control arms that hard to replace? I think I could tackle the guide rods myself...and may order some soon.

My suspension (even the shocks I believe) is all original at 250k...so just about everything could stand replacing. :o

Upper control arms are a breeze. I spent 45 minutes on each side. Subframe bolts are pretty safe to do yourself. Even if the subframe is not supported it will only hang down so much. There isn't much downward force at the mount points. Getting the bolts back on is a bugger. I used a bottle jack with a swivel head right underneath the bolt. I got both my subframe mounts for $48 bucks from Inter Auto San Diego. OEM too.

So what exactly is the process for replacing the upper control arms and rear subframe bushings....? :confused: I was looking at the explanation of it in the shop cd and it looks mighty complicated....I couldn't even understand parts of it....:eek: :dizzy2:

I think I might be able to pull off replacing the guide rod bushing assemblies....but the rest of it I am not sure.:o

Upper control arms are pretty simple. Make sure you hose down the UCA bolt w/ penetrating oil a every day for a few days before the job (it makes it a whole lot easier). It just bolts right on. Normally the UCA rest against a suspension stop to limit the travel so make sure the jack is not gonna slip, if it does, the spring will come flying out. I jacked the wheel off the ground with the jack under the lower control arm. Then everything else is straight forward. There might be a little downforce on the UCA from the sway bar, but nothing you can't muscle out of the way. Make sure you order 4 sway bar bushings too. Torque all three bolts to spec too, it's pretty important up there. It's really an straight forward job, I wouldn't worry about it too much. Good Luck!

Well, today I was going to head out for 75 miles on the freeway, so I checked my tire pressures and one was about 4lbs low...so I put them all up at 39psi, went on my drive...and it handled like it was on rails! :D :D Very cool indeed. So I guess I will leave my suspension alone for the time being....:wacko: :dizzy2:

I may still get an alignment sometime in the next few months....just because it has been over 20k since my last one.

I would start with ALL the rubber suspension bushings first and work your way up from there! Mine was doing the same thing when I bought it and I also had to replace a tie rod end on the passenger side. The rubber bushungs were more worn than anything else!:cool:

Well, I had to drive back to GR, MI today from Lansing MI, (74 miles) and it was very windy....needless to say, the issue I thought was gone, is BACK, and its BAD. :eek: I could barely keep the car in a straight line with tons of counter steering when wind gusts hit me! It was swerving all over the place. :dizzy2: :eek:

SO, I brought it right into the dealer, and low and behold, inspection was FREE! :eek: They took my car for 3 hours and had their top MB tech inspect everything to figure out the problems. He says: Replace left ball joint, its in bad shape with lots of play, right is fine (left front makes a thump now when turning, so I am getting it replaced ASAP) Also found: bushings tight and ok, steering ok, steeringbox had never been adjusted/tightened, so he tightened it up, eliminated almost all play in the wheel! Mind you, they did this free! He says I should replace the rear springs and shocks, which they told me before (my car sits low), and to have it realigned. So I ordered all the parts, two springs, two shocks, two spring bushings (14mm), and a ball joint for $337 They want $300 for the ball joint labor, and about $200-250 for the rear springs/shocks. Sounds fairly reasonable....I am going to talk to an INDY I know in Lansing tomorrow, if his price isn't much better, off to the dealer it goes. Considering they did 3 hours of free analysis and inspection + adjusted my steering, for FREE, I think I may just give them my business. I was amazed! :eek: :dizzy2:

Also taking place tomorrow morning, Valve adjustment, by me! :D

That little guy (the living Ronson add) wouldn't burn up so quick using diesel as an accelerate. :D