300D 1985 Rear spring height
 

What "should" the rear ride height be on a 1985 300D?

My car sits low, I think. Old springs? How ong do the spring last? My car has 192,000 miles, time to replace?

I think the shocks on that car bear a small amount of weight, probably enough to lift the rear back to originial spec. I just got a 1985 300D that sits low in back. The other day I put new Bilstein gas shocks on it and I had to put a jack under the rear shocks to push them up into place. I haven't taken the car down off the jack stands yet, but I expect the back to sit higher when I set it down. If your car has the original shocks, then a set of new Bilsteins will be just what the doctor ordered.

The last time I read anything about it 50,000 miles was considered the ' life ' of a spring... of course they can be rearched... or replaced.... they are not particularly expensive compared to the amount of rubber you can rub off if the height is affecting your front end alignment....
I am sure the factory lists the height the chassis should be off the ground at four specified places under the car.. if you find that you can just measure it...
Unless you have ' helper ' springs wound around the outside of your shock... the shock is not designed to be part of the lift of the car.. they are designed to dampen in different amounts against movement up compared to down....
While the self leveling shocks on some MB's will change ride height... if it is making up for the ride height in an unloaded situation... to make up for spring sag... then you are changing the ride characteristics of the car leaving the sagged springs in place..

Low ride height is also caused by worn subframe bushings. Shocks have no affect on ride height. I replaced mine with Bilsteins and they didn't make a difference.

GregS
'84 300D, 174k
'90 300Ce, 163k

Springs
 

I also have this problem, except that one SIDE of my car is lower than the other, or higher, depending upon your vantage point.