Sagging rear end on 1988 420SEL

[Timmy2]

Good morning! I'm the proud new owner of a 1988 420SEL. Seems generally to be in decent shape - pretty low mileage (about 75k on the clock) & pretty well maintained over all. Rear suspension is spring and shock absorber. Shocks aren't leaking and seem to be ok. Driving around town the car feels a little squishy and loose to me (but this is my first Mercedes so maybe that's just the ride?), but at highway speed this thing is solid like a rock. Amazing.

But the rear end looks low to me - like maybe 1-2 inches. I have zero experience specifically with Mercedes, so I need some help here.

My first suspect is those bushings that connect the differential / final drive to the rear sub-frame. There appear to be two. What do you guys think of this?

And / or maybe at 30+ years the springs are tired? But why only the rears?

I look forward to whatever thoughts / advice anybody wants to offer!

Thanks.

[Frank Reiner]

T2:

Empty trunk & 1/2 tank fuel.
Ground-to-lip of wheel arch @ center of wheel: 25 1/4" to 26".

[Usaguy]

Originally Posted by Timmy2

My first suspect is those bushings that connect the differential / final drive to the rear sub-frame.

diff bushings do not affect the height. The 2 subframe mounts in the front and 1 in the back do.

Originally Posted by Timmy2

And / or maybe at 30+ years the springs are tired?

These cars have rubber pads on top of the springs and they can wear out over time. Count the number of burrs on them when replacing. You can get taller ones.

Also W126 have soft springs in the back. In my 300SE I can easily tell when I have a full tank just by looking at the rear suspension. So if you like to carry a lot of junk in your trunk the car will sag. In the US the 560SEL/SEC and I think some 350SD/SDL had SLS to take care of this problem

[nulu]

Replace the rear springs , there are many variations, it would be in your best interest to take one out and send it to a spring manufacturer and tell them you want it to sit higher, I work at a dealer for 30 years been there done that with that exact model, we had to order twice and still was too low , finally with taller rubber pads it was right . It would be easier just to get them measured and made, they do just sag over time in the rear

[Timmy2]

Thank you!

I'm now looking at pics of 450s and they all look sort of down at the back. So maybe it's the look...

After taking everything out of the trunk except the spare and its a full tank of gas the rear is sitting at about 25 1/2" or 25 3/4", so that's about right.

How's about the front? Currently it sits around 26 3/4". Is that correct?

Pads on top of the springs have 2 burls and the rubber that I can see looks ok.

[Frank Reiner]

Originally Posted by Timmy2

How's about the front? Currently it sits around 26 3/4". Is that correct?

That's an OK height.

[Timmy2]

Ok. Thanks. Much appreciated.

[pawoSD]

Mine had the same issue when I got it years back. Was also a super well maintained lower miles example (115k). I replaced the rear springs/shocks/spring pads and it restored the normal ride height.