Ride height question / New shocks on a 1991 190E 2.6 (154k miles) - PeachParts Mercedes-Benz Forum

brookspw · #1 08-04-2003, 04:42 PM

Summary:
-- car runs great
-- it looks even better
-- I bought it 2 years ago for $5,500 (had 110k miles)

At issue:
-- needs ball joints, might as well do tie rods
-- MB Independant Tech says that worn shocks are the reason for the outside feathering on my tires.

1. I like the "lowered" look that I have. It isn't lowered, it is actually just "sagging", because the shocks are dead.
2. I did a search and heard nothing but bad experiences where shocks were replaced and the ride height increased 1.5 to 2" (yes, actually just back to "new" ride height).
3. What can I do to replace the shocks but not to raise the ride height?
4. I don't want to get into replacing the shocks with lowering shocks.
5. I don't know what bump spring pads I have, but I could go to the thinnest pad, but would have minimal effect if shocks raised it 2".

Suggestions or observations?

Thanks everyone.

haasman · #2 08-04-2003, 05:27 PM

Here are my 2 cents ....

Feathering on the outside of the front tires can be caused by shocks but more than likely it is worn sway bar bushings, front and rear, and/or alignment. Cheap, easy to do, and results you can feel immediately. An easy DIYer, a Saturday morning project.

I will ONLY take my cars to a Mercedes dealer for an alignment. This alignment would include the use of a spreader bar, it supplies a preload that mimics the car going down the road.

Shocks- depending on the brand and model, some shocks do seem to lift the car for a while, some settle right back down. I think this is a result of stiffer seals and being pressurized.

Both the 300E and the E320 wagon (fronts) in my opinion experienced a chassis rise. Both cars got Bilstein HDs which are great, BTW. Through the years I have been disappointed by many different brands of shocks including KYB etc. I recommend either Bilstein or Boge brands.

I think .... (notice here lots of opportunity for comments from the Forum members) .... that from the least to greatest influence in ride height change with new shocks would be as follows:

Boge (OEM), Bilstein Comfort, Bilstein HD …..Bilstein Sports are the same as HDs but made for shorter springs.

You can adjust the ride height via spring pads. I was confused about the effect of changing the pads and the resulting height effect until one wise member on this forum pointed out that the spring pushes approximately half way on the control arms, therefore an increase or decrease of the spring pad translates into roughly 2x ride height change. Hmmmm....

You don't want to go too low .... check and see which bump pads you have in there now, front and rear. If it were my car I would look at one pad thinner front and rear.

In final opinion, it seems to me about 1990 Mercedes changed springs and possibly spring pads on the 201 and 124 series. It is my observation so far that ride height issues rarely come up on cars prior to 1990.

OK, maybe a little more than 2 cents ... hope this helps.

Haasman

brookspw · #3 08-04-2003, 10:34 PM

Thanks, Haasman.

1. Can you walk me through the replacement of worn sway bar bushings (and, what they should look like and how I'd know if they were indeed worn)? The feathering is only on the outside of the FRONT tires, would the REAR sway bar bushings affect this?

2. Can you walk me through the R & R of the shocks, front and rear? I'll post back this Saturday what thickness my coil pads are.

I don't want it lower -- I want it to look just like it does right now.

I'd love to hear more experiences from those with 1991 and later 190 2.6 -- especially those that had NO higher ride height.

Thanks for taking the time,

Phillip

haasman · #4 08-05-2003, 02:11 AM

Phillip

Replacement of the sway bar bushings is easy.

Fronts: There are four bushings that need to be replaced: Two outboard and two inboard.

You will need to remove the two U-clamps that hold the bar to the body of the car. I believe they are 13mm bolts. Inside, between the bar and the U-clamps are the bushings. Outboard, you will need to remove the caps that hold the bar ends to the control arm. Inside again is the bushing.

I drop the whole bar before trying to remove the bushings. The old ones should slide off easily. Before installing the inboard new ones, use a rag and clean the bar of any road grime, as you don’t want that wearing on the new bushing surfaces. The newer bushings do not need to be lubed. The newer bushings are telltale because they have a little liner (inside) with micro-groves all around end to end.

Install the bar with the new bushings to the body first, then do the outboard ones by the control arms. Ideally, tighten firmly once the car is on level ground as to avoid any pre-load on the bushings.

Rears: There are only two to replace. They located the bar to the body. The ends connect to the rear suspension via vertical plastic links. While you are there, check to make sure there is no slop with the links.

It is easiest to jack up the whole rear-end, but one side at a time will work. I believe again the U-Clamps or caps are held in by 13mm bolts, two per side. Once both sides, four bolts are removed, the bar can be pulled away from the body mount enough to get the rubber bushing out.

Again clean the bar prior to replacing. The bushings are split to facilitate getting them on to the sway bar. Some people do lube here with a little silicone.

I always use a good paste lube on all the sway bar bolts. They often are not removed for years and 10’s of thousands of miles.

If you have any doubt as to whether the bushings need to be replaced, compare the old ones with the new ones. Often rather shocking how elongated the holes become.

Which bar (and bushings) influence which end of the car? It is said that the rear sway bar and bushings is most often felt in the front, and visa versa. BTW, do both the fronts and the rears.

Shocks: There are many threads regarding shock replacement on the 190s. The rears are easy. I can now replace both rears in less than an hour, often a little more than 30 minutes.

To do the rears: One side at a time works. Jack up a corner. Rip out the trunk liner on one side, by starting at the tail light and carefully pull it out. You want to uncover the upper shock mount that has two 17mm nuts, one on top of another holding the top of the shock in. For the bottom, use a 10mm socket to remove the two or three small short holding bolts of the plastic lower control arm cover. Often after all these little bolts are removed, yanking the leading or trailing edge enables the cover to come off easily. Once uncovered, you will see the bottom of the shock that is held into the control arm by either a 17mm or 19mm nut and bolt. Remove the bolt. Once removed you can move the shock bottom easily for removal.

Fronts: Technically, because the EXTREME danger of the coil spring, you should use a spring compressor to hold it. The front shock is a strut. It is held in the top by a large nut and at the bottom by three, I believe 19mm bolts.

Some people have jacked their car up, put it on jack stands, then used the jack with a block of wood for protection, and lifted under the front A-arm to take the pressure off the strut to remove. This can be very dangerous. Car springs kill people.

You might want to check the upper shock mount while you are there. Any sign of splitting of the rubber, replace.

User Locktite on all the shock bolts. Be sure to tighten the bolts firmly. This is, after all, your suspension.

Haasman

brookspw · #5 08-05-2003, 05:01 PM

This is a perfect example about what is so good about this board.

I appreciate the info from everyone. Take note, however (me included), at the step by step type instructions. This is so integral.

Any other opinions/experiences out there concerning the ride height issue?

MTI · #6 08-05-2003, 06:02 PM

Can't recommend www.2phast.com for pics and text on his chassis work on his 2.6L. I'm sure you'll find it a great help.

brookspw · #7 08-05-2003, 06:58 PM

Height. I'm looking for RIDE HEIGHT answers/experiences.

MTI · #8 08-05-2003, 07:21 PM

Over on www.190Revolution.net in the wheel & tire forum, you'll find the listings of various members wheel, tire, spring and shock combinations that might help you.

You'll have to understand that ride height is somewhat subjective and given the age of our cars, will vary from car to car.

#9 08-06-2003, 08:26 AM

In most cases shocks have little or nothing to do with ride height. The only cases would be if you are replacing gas shocks that have leaked the gas so that they no longer have any pressure.

If both tires on the front axle are "feathering" as you call it on the outside or the inside, this is in all likelihood due to misadjusted toe.

Good luck,

brookspw · #10 08-06-2003, 09:49 AM

Thanks, Larry. My car has the original shocks, so I wouldn't be surprised if they are bad. However, would my shocks be the gas type you are mentioning? If not, you are saying, I should not experience an increase in ride height with new shocks?

Just wondering, because if you do a search for shocks and 190 you'll see many instances of the ride height increasing.

As far as the feathering, is there a "cheap" or easy way to check that. If that is the problem, I'd rather just fix that instead of new shocks.

Thanks

#11 08-06-2003, 12:00 PM

Yes, the OE shocks are gas and yes they can lose pressure over the years.

The toe can be checked in the driveway, but there are several things that must be done to get an accurate measurement.

Raise each wheel and use a jackstand with a nail clamped to it as a fixed position pointer to scribe a line all the way around the circumference of the tire. This does away with the inaccuracy of the tire mounting variations around the tire.

After scribing both tires, let it down and roll the car at least two rotations of the wheel to settle the suspension. Measure carefully the difference between the two scribed lines front and rear at the same height off the ground. Adjust so that these measurements are exactly equal.

Good luck,

brookspw · #12 08-06-2003, 03:44 PM

You had me at "Hello".

Are you saying to measure the distance between the front tires at a position at the rear of the tire (1/2 way up) to the same position across the car to the other tire, and then the same across the front of the front tires -- then make them be the same?

If so,

1. I lost you on the baseline deal of scribing around a tire first.
2. What do I adjust to adjust the toe?

Also -- I guess you are saying that my car will be higher, then, with new shocks. I don't want that -- what can I do?

Thanks

#13 08-06-2003, 04:11 PM

The line is scribed to give a measuring point that is true with the wheel. You roll it a few tire rotations to let the suspension settle out after lifting.

You can't measure halfway up the tire because the body will be in the way. You measure as high as you can without deflecting the measuring tape with the chassis of the car and about the same height on both sides. You are measuring between the scribed lines. You adjust the tie rod sleeves to adjust the toe. Loosen the locking clamps then turn the sleeve to adjust toe. If you adjust half on each side you will keep the steering wheel centered. After adjusting MAKE SURE YOU RETIGHTEN THE LOCK CLAMPS.

Good luck,

brookspw · #14 08-06-2003, 04:20 PM

Thank you, I believe I understand now.

The scribe line is on the tread area / not the sidewall.

Is there an acceptable variation, or is any measurable difference too much?

Have you seen a "perfect alignment" still allow feathering due to bad shocks?

What about my new shocks/ride height question?

Thanks very much.

brookspw · #15 08-09-2003, 11:37 AM

Quote:

Originally posted by LarryBible
The line is scribed to give a measuring point that is true with the wheel. You roll it a few tire rotations to let the suspension settle out after lifting.

You can't measure halfway up the tire because the body will be in the way. You measure as high as you can without deflecting the measuring tape with the chassis of the car and about the same height on both sides. You are measuring between the scribed lines. You adjust the tie rod sleeves to adjust the toe. Loosen the locking clamps then turn the sleeve to adjust toe. If you adjust half on each side you will keep the steering wheel centered. After adjusting MAKE SURE YOU RETIGHTEN THE LOCK CLAMPS.

Good luck,

LarryBible -- I will do this today. 2 Questions:

1. Using the fixed scribe -- how can I assure that I have the wheels straight enough to get an accurate reading? If I have them off center by any measurement, won't that throw it off?

2. If measurement is off -- how do I know which wheel it is, OR, if it is both? (Both have wear, left moreso than the right.)

Thanks, Larry