Suspension and straight line stability question
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94 E320 Wagon
Suspension and straight line stability question
I recently purchased a 1999 E320 wagon with 128K for my wife. When I test drove it I noticed that the front (and possibly the rear) suspension seemed a bit harsh. I assumed that it needed lower ball joints to freshen it up. I recently took it in for a tranny service and I asked the mechanic to take a close look at the front end and told him what I suspected and he said he would check them but that I was probably right about the ball joints at 128K. When I picked up the car he said that he checked them and found them and the rest of the suspension to be surprisingly tight and in good order. I haven't had a chance to look at them myself but he seemed pretty sure that they were solid.
So here is my problem and my question: It has a pretty harsh feel to the front end over expansion joints. It doesn't really make a lot of noise but it just doesn't seem to soak up bumps very well. It also doesn't seem to run a straight line on the highway like I would expect. It isn't hard to drive or anything but I would expect an effortless straight line from this car. I have not had it aligned yet but the steering wheel is centered and it doesn't pull to either side. I was planning to fix the harshness problem and then have it aligned. It has a very recent set of Michelins and I am running 36 PSI rear and 30 PSI front. Anyone have any ideas?
So here is my problem and my question: It has a pretty harsh feel to the front end over expansion joints. It doesn't really make a lot of noise but it just doesn't seem to soak up bumps very well. It also doesn't seem to run a straight line on the highway like I would expect. It isn't hard to drive or anything but I would expect an effortless straight line from this car. I have not had it aligned yet but the steering wheel is centered and it doesn't pull to either side. I was planning to fix the harshness problem and then have it aligned. It has a very recent set of Michelins and I am running 36 PSI rear and 30 PSI front. Anyone have any ideas?
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From: SoCal
98 Brilliant Silver E320 Wagon
Ride is related to alignment somewhat as is tracking. A quality 4-wheel alignment at the dealer may help.
Ride harshness may be noticeable if you were previously used to a softer riding car such as a Buick Roadmaster.
You may also want to check the self-leveling suspension system to see if it's working correctly.
Ride harshness may be noticeable if you were previously used to a softer riding car such as a Buick Roadmaster.
You may also want to check the self-leveling suspension system to see if it's working correctly.
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94 E320 Wagon
I was figuring on doing an alignment but I thought I would make a few repairs first. As it turns out, I'm just not sure what those repairs should be.
I realize this is no Buick Roadmaster but I am certain that it is a bit more harsh then it should be. The self leveling system is fully functional although I plan to change the fluid in it as soon as I get a chance. I've also thought about adjusting the lever to give it just a bit more ride heighth in the rear. Mine appears almost level with the front and I'm guessing it should be slightly higher.
I will get a chance to look at the suspension myself before before long and I'm hoping to find some worn bushings or something that I can replace to bring it back up to par. Anyone else that has had the same problem is encouraged to send some ideas my way.
I realize this is no Buick Roadmaster but I am certain that it is a bit more harsh then it should be. The self leveling system is fully functional although I plan to change the fluid in it as soon as I get a chance. I've also thought about adjusting the lever to give it just a bit more ride heighth in the rear. Mine appears almost level with the front and I'm guessing it should be slightly higher.
I will get a chance to look at the suspension myself before before long and I'm hoping to find some worn bushings or something that I can replace to bring it back up to par. Anyone else that has had the same problem is encouraged to send some ideas my way.
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From: Pittsburgh,PA, Cambridge, Ontario, CN
2003 S210 3.8L Brabus wagon
[QUOTE=Goofaroo;4774537]I was figuring on doing an alignment but I thought I would make a few repairs first. As it turns out, I'm just not sure what those repairs should be.
Check the brand of shock currently in the car. It may have been changed from stock. Ball joints would be a good start if there is play and have not been properly lubed. As for the SLS a change in fluid could be good although not required. The system levels the car so front and rear remain at equal and horizontal ride height with no rake. The rear comes up and back to level as the rear load is increased. The only adjustment required would be if the vehicle is lowered significantly and then the adjustment arm should be set to the S position for sport suspension as in the case for the W210 Estate E55 in Europe. Outside of that I would just maintain and do an alignment as recommended and check the quality of your tires for signs of age and proper inflation. best wishes.
Check the brand of shock currently in the car. It may have been changed from stock. Ball joints would be a good start if there is play and have not been properly lubed. As for the SLS a change in fluid could be good although not required. The system levels the car so front and rear remain at equal and horizontal ride height with no rake. The rear comes up and back to level as the rear load is increased. The only adjustment required would be if the vehicle is lowered significantly and then the adjustment arm should be set to the S position for sport suspension as in the case for the W210 Estate E55 in Europe. Outside of that I would just maintain and do an alignment as recommended and check the quality of your tires for signs of age and proper inflation. best wishes.
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94 E320 Wagon
I am not as concerned about the rear as I am the front. I looked at shocks online and I am thinking about ordering some new ones. I would like to put in a pair of shocks now and see how much that helps and then do a more in depth service this fall with bushings and ball joints. I am kind of suspecting that maybe the bushings and rubber mounts on the existing shocks are worn out and causing some of the harshness.
For anyone who has changed their shocks- do I have to compress the springs to change the shocks or can I just block under the control arm and change out the shocks with the springs in place?
For anyone who has changed their shocks- do I have to compress the springs to change the shocks or can I just block under the control arm and change out the shocks with the springs in place?
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From: Südflorida
'99 E430, '05 ML500, '15 GLK350
Worn shocks don't tend to produce harshness, more like mushiness and excessive springing.
Are they the stock 16" wheels and tire sizes? I think the recommended pressure is lower for your car - look on the label inside the driver door.
As far as the wandering, all I can say is at about your mileage I replaced the ball joints, tie-rod ends and front wheel bearings, and between them all (with alignment afterward) the tracking was improved considerably. These are straightforward DIY's if you want to save some money.
Are they the stock 16" wheels and tire sizes? I think the recommended pressure is lower for your car - look on the label inside the driver door.
As far as the wandering, all I can say is at about your mileage I replaced the ball joints, tie-rod ends and front wheel bearings, and between them all (with alignment afterward) the tracking was improved considerably. These are straightforward DIY's if you want to save some money.
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From: Pittsburgh,PA, Cambridge, Ontario, CN
2003 S210 3.8L Brabus wagon
For anyone who has changed their shocks- do I have to compress the springs to change the shocks or can I just block under the control arm and change out the shocks with the springs in place?[/QUOTE]
Springs do not need to be compressed to change the shocks.. check the things mentioned above and you will solve your issues.
Springs do not need to be compressed to change the shocks.. check the things mentioned above and you will solve your issues.
