suspension question - PeachParts Mercedes-Benz Forum

Benz300 · #1 02-28-2004, 07:42 AM

If the rear of the car is lower than the front, meaning the space between the tire well and the tire is less on the rear than the front, does that translate into worn springs or should the shocks be checked as well ?
I've always heard that for performace the springs are replaced to lower the car which makes me think that the springs could've gone bad with age in the rear. is that so ?
thanks for the replies in advance.

stevebfl · #2 02-28-2004, 11:46 AM

Your testing mechanism is not appropriate. The fender wells front and rear are different and the gauging you are doing would not be accurate.

Except that your eye knows something is wrong, probably right. The height is mostly determined by the springs but I have heard that each GOOD shock holds 75 lbs. So if you have a bad shock it would be similar to placing a 75 lb weight at on that fender.

I'm guessing that springs will be the answer.

Benz300 · #3 03-03-2004, 06:16 AM

thanks for the reply steve,
well the reason i ask is because my car is sitting low in the rear, as if one has tons of load in the trunk. everytime i take it to the dealer to get the shocks checked, they say they checked out fine. is there some test that the dealer makes the shocks and springs go through to figure out whether they're under specs or not ?

wbain5280 · #4 03-03-2004, 06:30 AM

How do springs wear out? It's a steel rod wound into a coil.

#5 03-03-2004, 07:57 AM

1. Springs don't wear the way a bearing does, but the metal is tempered to achieve its springiness in a way which does often result in a gradual loss of strength over the years as the internal molecular structure changes, so they sag a bit. I'm sure real engineers will quibble about the way I stated that, but those of us who are old enough to remember the big GM cars of the '50s surely can recall how Oldsmobiles and Buicks used to get an inch or so lower by the time they were 5 years old -- Ford fans like my Dad always blamed the coil springs and insisted that Ford should have stuck with leaf springs at both ends, but he mistook Ford's superior metalurgy for something in the nature of coils.

Of course, wear in the bushings and rubber spring shims can cause a slight lowering, too.

2. Gas-pressure shocks do support some weight, whereas the old style don't, so a car with gas shocks will lower slightly as the gas leaks away, even though the fluid damper effectiveness of the shock has not yet changed noticeably.

wbain5280 · #6 03-03-2004, 08:24 AM

Quote:

Originally posted by Fimum Fit
1. Springs don't wear the way a bearing does, but the metal is tempered to achieve its springiness in a way which does often result in a gradual loss of strength over the years as the internal molecular structure changes, so they sag a bit. I'm sure real engineers will quibble about the way I stated that, but those of us who are old enough to remember the big GM cars of the '50s surely can recall how Oldsmobiles and Buicks used to get an inch or so lower by the time they were 5 years old -- Ford fans like my Dad always blamed the coil springs and insisted that Ford should have stuck with leaf springs at both ends, but he mistook Ford's superior metalurgy for something in the nature of coils.

That gradual loss of temper over they years would imply that the metal is getting hot in order to change the molecular structure. I would think the rubber spring seats might be compressing over time.

IMHO

psfred · #7 03-03-2004, 09:35 AM

No, the spring simply bends and goes "flat". Coil springs are more likely to do this than leaf springs, but their other characteristics more than make up for the sag problem.

Peter

sbourg · #8 03-03-2004, 09:37 AM

Rear shocks on your signature models are a pretty easy R&R. Off the car, it would be possible to check them for problems that can't be isolated readily when installed.

Steve

Benz300 · #9 03-11-2004, 09:20 AM

while I'm debating the idea of replacing the springs, I've also thought of lowering the car a couple of times. Can I leave the stock shocks in place and replace the springs with lower sport springs. I like the way the car handles at the moment and don't need stiff suspension. I just want to lower the car because the early 124's have a little more spacing between the wheels and the body than the later 124 models. So if all I need is to lower the car and keep the soft suspension stock, what type of springs can I replace the original springs with ? keeping in mind that I dont want to stiffer suspension that people acheive changing the springs to sport ones...

J.HIDALGO · #10 03-11-2004, 09:35 AM

I will give you mininal change in height but, since you want to lower it. Another option is the Sportline conversion which will lower you ride but, to MB standards, since it is a factory mod.
Just in case you did not see this:
http://www.peachparts.com/sportline_suspension.htm
Good luck!

Benz300 · #11 03-11-2004, 09:50 AM

Thanks, I had read the doc in the past. However I'm not looking to do major conversions. I like the ride quality as is. just want to lower it about 2 to 2.5 inches keeping everything else the same. would changing the shocks give me the required results ? if so what brand shocks should i be using that won't affect the ride quality ?