How to put car on jack stands to check clunking sound?
 

My car has been having clunking sounds when going through potholes.. I have been meaning to check it, but haven't found a good way to check if it is the sway bar bushings or others..

How should I put my car on jack stands? I have something similar to these jacks below:

http://www.harborfreight.com/3-ton-h...nds-38846.html

I also have ramps and hydraulic jacks.. I put the car on the ramps and did a quick check.. All the bushings seem tight and have no-crack, but I think a more representative check would be to put it on a jack stand so the wheels are not loaded..

Any suggestions? I am aware of the jack pad adapter, but I am not sure how I should use it with the jack stand.. Should I just get the modified jack stand they sell? Other alternatives?

I usually put them under the car.

Those stands have a pretty deep saddle. I used blocks from http://reverselogic.us/ReverseLogicLimited/Home.html and I think the saddle is too deep for them. I just noticed that they have stands with integrated blocks. That might be an idea. There don't seem to be any jackpoints on the car other than the official ones. Be careful!

jack your car up in front in the middle and place the jack stands on sides where you can jack the car from the side. if you look under your car in the middle you'll see a flat spot where you can place the jack.

Have you checked to see if your struts/shocks have gone out? with the car on the ground press down on each corner of the and the car should rebound right away and feel sloshy or keep bouncing. .

Did a quick look around. Was able to find this for you.

https://mbworld.org/forums/attachmen...g_points_w.jpg

Thanks for the replies everyone! I think I need to clarify my question..

hahahaha...

Yeah this seem to be the problem.. I have tried jacking it up from the center of the car, but I wasn't sure where to put the jack stands.. The plastic pads didn't seem like it would hold it without some sort of custom adaptors.. I am not sure if the one from reverselogic would work with my jack stand.. Have anyone faced this problem? How does everyone else do it?

Thanks for the picture! Yup I have jacked it up there too.. I am just not sure where to put the jack stand..

Yup.. How do you put the car on the jack stand? Will the pad hold with the kind of jack stand I have?

I will check the struts/shocks.. They seemed fine when I checked earlier in the year..

It doesn't seem to be the strut.. Car bounces fine and it doesn't vibrate on the highway..

Does anyone else have any inputs? How do others put their car on jack stands?

I always had issues putting my w203 on jack stands. Once one of my rubber peices broke off and the car almost fell down on my and Iv just given up since. Before I would just use the rubber jack points to jack up the car and then put stands near then under the car were that plastic strip runs. It was a bad Idea because it started cracking and just doesn't seem safe.

I use a pretty hefty hydraulic garage jack under the front. There is a rubber lifting point, center front, abou a foot behind the bumper. In the rear I use the differential housing. I dont use jack stands but a number of 6x6 and 4x4 pieces, a foot long each, to support the car at the 4 normal rubber jacking sites on the sides.

+1 on floor jack and lifting points ... rubber block under engine brace in the front, and differential in the rear. PUT A PIECE OF WOOD in between the jack and the car when lifting. A 6" piece of 2x4, or 1/2" or more thick plywood, will work nicely. The wood will soften the pressure point and avoid damage to the car, especially the differential.

As mentioned, the jack stand mount locations are the same as the single-tire lift points -- the plastic blocks under the side rails of the car, fore/aft of the rear/front wheels. Again, I suggest putting a wooden block between the jack stand and the mounting block. I have both 1/2" plywood blocks and pieces of 2x4, depending on the height I need. you need about a 4"x6" piece of wood to comfortably cover the rim of the plastic block that surround the cavity. The wood will dimple where it needs to to absorb the weight of the car, then it should hold pretty well.

I turn the jack so the saddle is perpendicular to the car, so the pitch of the car when lifted doesn't affect the jack making full contact with both prongs of the saddle.

As an added measure of safety I leave the floor jack under the lifting point with just a bit of pressure on it. I also set the tires under the car just behind the jackstands, to keep the car off the ground should the jacks fall over (I'm in California ... you never know when the next earthquake will hit).

I've lifted my car now a few dozen times for brakes and suspension work over the past 6 months ... so far no problems other than my aching back ...

As for the noise, I suggest you check:

* sway bar links. On my son's Honda Accord these seem to make a lot of noise when driving over sharp bumps at 30 mph. I don't know if the Mercedes have the same symptoms. You can also tested by putting a bunch of 1x6 pieces of wood on the street and have someone drive over them at 15-20mph as you listen closely ... once you get the suspension moving quickly enough you would hear the noise.

* upper strut mounts. it's a rubber piece that looks like a small bundt cake, and fits under the wheel well at the top of the strut. If you lift the car up, check from the engine compartment with a flashlight and look into the top of the strut mount. There's a bit of space where you can see the top of the rubber. If the mount is worn you may see separation cracks in the rubber. But the load must be off the suspension to see the cracks.

* control arm bushings. Given enough of a "jolt" it's possible you can bottom those out. As was mentioned, if you raise the car off the suspension and look at the bushings you should see cracks in the rubber if they are worn. Also, does the front suspension feel squirly at all or make a knocking noise when you brake hard to a stop?

* tie rod ends. Have someone jiggle the steering wheel back and forth a bit, to see if the ball joints on the tie rod ends move at all before turning the wheels.

* struts. Hate to say it, but moving the strut piston slowly and moving it very abruptly can produce two very different results. One way to check out the struts is to drive over a parking lot speed bump at 5mph, enough so that the car gets a nice big bounce up and then down. If you hear the struts wheezing and the car feels like it's laboring over the speed bump and over-rebounding on the way down, then your struts may not be damping well enough. If the car bumps taughtly over the speed bump with no noise or excess movement, then you're good.

* Brake pad retaining clips ... are the pads held in tight with the spring clip? If not, possibly the pads are loose enough to rattle over sharp bumps.

How many miles on the car? If the suspension is original and you are nearing 100k miles or several years, then it may be time to go through it all and refresh.

One thing to note -- there are some dependencies on R&R for these pieces:

* In order to replace the strut mounts you have to dissasemble the strut assembly, so might want to replace struts at that time. And vice versa.

* In order to replace upper control arms you have to unbolt the strut from the steering knuckle ... so if you are going to work on the strut or strut mounts, you may want to replace the upper control arms at that time.

Lower control arms and sway bar links can be replaced independent of the others.

Jack stand.
 

Jesus ****ing Christ proofread your ****!