steering?
 

I have an 82 300TD. Yesterday, on the highway, I heard a soft thud from under the car...about where a front passengers feet would be. Almost sounded like something had fallen off the bottom of the car. I pulled over, gave a quick look under the car but didn't notice anything strange.

Over the next hour of driving I noticed these things:

-The steering was now pulling towards the right
-Its possible that there was a hum/road noise from the front wheels that I had never noticed before...although I don't know if it's always been there and I was just being hyper alert?
-Once I had to make a quicker movement with the wheel and it felt like the car got away from me for a second
-A few times I heard a clanking noise from the vicinity of the front passenger wheel. Both times it was at slower speeds while making a turn, and may have co-incided with hitting bumps...but not sure

Something obviously happened, but I'm not exactly sure what/where to look? Any thoughts?

Might check to see if your ball joints have collapsed....
or that some bushings have given way.... I am thinking of those on the A arms... at the frame....
crawling under there with a good flashlight might help...
When were your wheel bearings checked last ?

Jack up the front and support on the frame rails, on jack stands. I sometimes use a lattice of short 4"x4" wood, which looks safer to me.

Push & pull all the wheels, looking for any play in the ball joints, strut rods, and steering linkage. Have a helper turn the steering as you look. Should be obvious what broke.

With it up on stands, slip a metal pipe under the tire and pry up to check ball joint play. Or A-arm play I guess, yikes. You can pry other places too, but leverage really helps.

Over the years I've learned to hit everything at once after something goes. That play stresses and weakens other components and it becomes an every weekend project for awhile.

It's not bad to do, impact and ball joint separator help. And a big ****** hammer.

That was something I learned working at a front end shop..... do everything which is not already new .... has the advantage of making a front end alignment possible too.....
and New Springs are easy to do at the time you have everything apart...and if you read the current new spring thread... people are always pleased they ' sprang' for new springs.....LOL

steering?
 

Haha. There's a thread around here of a guy that replaced his front springs only to find out how much to rear were sagging. Looked like an old Impala on hydraulics. Motivated me to do the rear first.

Going off topic again.

If you (op) replaces balljoints or tie rod ends its important to buy quality. You should notice a drastic price spread. The difference being the cheep ones are metal on metal contact, the better have a coating in between (Teflon?)

Looking at grease zerks will give backwards results. The cheap have a grease option, the better usually don't as there isn't metal contact in there and the coating lasts long enough.

That being said, I have done the cheap ones on a 90 4Runner with a 3.0 motor and massive rust. Just a roller. I kept the ball joints greased and had to install zerks on the tie rod ends. I would bury that truck to the hood in river crossings and grease regularly.

Prob not helpful here, but I RTV'd the outside of the hub and made sure the inner seals were good. And kept the backing plate drain holes clean.


What's the test for upper ball joints? I remember lower is prying up on the tire but to check the upper you pry on the control arm (up)? Since it will be resting on the ball?

Does his car have uppers? Lol.

I have found that whoever you buy front suspension parts from it is worth checking under the rubber boots for grease before you fit them.

I even found an almost dry TRW part that I had bought from the MB dealer.

As for the problem =>

First step - weight on ground - grab hold of each wheel and see if you can pull it off the car! Give it a good tug!

sorry for the long delay. only just got to go look over the car with all your ideas today. jacked up the front end and pulled on the wheels a bit. didn't notice anything unusual. am i supposed to pull front to back or side to side?

i wasn't able to try prying the wheel with a long bar because the only place i had to work on the car was a parallel parking spot with not much room in front. i also didn't have a helper to turn the wheel while i looked. tomorrow i'll get both those thigns and find a parking lot where i can spread out.

when i put the car back down i could see that the FR wheel is definitely leaning in at the top.

i guess i'm wondering how many of the possible scenarios could be an easy DIY fix? Normally I'm up for the challenge but right now myself (and the car) are in NYC...and it seems difficult to find space to work on a car...in the winter. from the threads i've been reading it seems like most scenarios might involve specialty tools of one or the other?

in any event, i'll take the car to a parking lot tomorrow and hopefully have more updates...

if you can remove the wheel, inspect the swaybar/bushings & upper control arm.

the swaybar is prone to rust and breakage between the bushings where it connects to the arm.

It can be a challenge to get the ball joints out. Looks like your upper failed. When removing and replacing you can use a pickle fork and pound it in. When reusing they make a balljoints removing tool.

It can be done though. That pickle fork is cheap to buy. Or even rent. Just pound away. The nuts can strip holding the top side. Then you have it apart and are in trouble.

I would say be careful driving it. I've had one come apart before.

I would not drive the car until the issue is found and repaired. The consequences of doing so can be bad sometimes.

Your description tends to indicate something has gone bad in an important area.

I would inspect the upper torsion bar to which the upper control arm is attached. With the wheel leaning in, (and did he say it was on the curb side), it sounds like the torsion bar under the battery box might have corroded to the point of near total failure. Don't drive it until you check. Remove the battery, and the ledge that the battery sets on. and right under there is a real problem area. Look at it!

I wonder if you have had a massive failure of the inner (pivot) bushing on the upper control arm/balljoint. This happened to me earlier this year. I did not notice anything was wrong until I pulled the wheel to do something else and realized the tire was rubbing on the shock. (Where I park I never see the front end of the car straight on, and you don't notice the lean as much when looking at the wheel from the side.)

The disintegration of the bushing would account for a clunk.

I am attaching a pic of a new control arm/balljoint with a worn one beside. This is not from my car, the bushing had failed way worse on my passenger side. It's just to give you an idea.

If this is the issue, it is a just-do-able job outside in current northeast coast conditions, if you have to work that way. But just, for someone doing it for the first time. But recruit a second set of hands and find a place where you won't be rushed.

There are a few DIYs floating around that contain the instructions on how to do it, but some cover it in the context of a more complete front end rebuild. Have a look at this one for starters: http://dieselgiant.com/mercedes_upper_control_arm_repla.htm

so i guess i see what is wrong. i'm not very familiar with front end stuff but judging by zacarias' picture i'm assuming this is the upper control arm. in comparing it to the control arm on the other side, it almost just seems like the nut the held the second bushing fell out...and the bushing along with it. could it possibly be as easy as forcing everything into alignment somehow and just putting in a new nut/bushing? what is the name of the part that disattached itself from the UCA?

Yep, you lost the bolt that holds the torsionbar/bushing assembly to the upper control arm. That's a known rust and failure area so hopefully the torsion bar is not buggered and the internal threads are still good.

It looks like the bushing in the upper arm where it passes through the body is failing, also. You can probably buy the torsion arm bushings, washer and bolt separately, but if it was me, I'd go ahead and buy the kit and replace the entire arm. The worn upper bushing probably contributed to you losing the torsion arm hardware. I'm not sure if the bolt comes with the kit--you might have to pull the one on the other side to get a size, or maybe someone here knows.

You need to check the other side anyway, as chances are it is worn, too.