saggy rear on my 126! - PeachParts Mercedes-Benz Forum

126nut · #1 08-30-2004, 01:31 PM

I have replaced the coil springs and it still sets low in the rear. I am just about ready to put some of them there redneck coil spring spacers in it to nudge it back up, forbidden maybe yes but I am really frustrated after all the money and time I spent on it and the problem is still there.

Now I see why they strted putting the somewhat troublesome hyraulics on them. I hauled the relatives around one weekend and think I may have almost ground a hole in the spare tire well, it was dragging that bad.

Maybe some air shocks? Seriously, would air shocks do the trick? Any applications available for my 89 420SEL, would ya think?

Brian Carlton · #2 08-30-2004, 08:34 PM

I've got the same issue on the SDL. I have not replaced the springs yet, but am planning to do so.

Some questions:

Have you measured the height of the fenderwell above the ground, before and after the spring install? Mine is currently at 24.75 inches prior to the spring install. This is about 2.25 inches less than the front.

Did you change the rubber bushing that sits above the spring?

What is the condition of the subframe mounts? These can give up .75 inches if they are mashed flat.

I sure would like to avoid wasting my time with springs if there are other, more important variables.

126nut · #3 08-30-2004, 10:03 PM

I guess maybe I should have checked out the rubber spring perches a bit more. I have also heard about the subframe mounts but am not exactly clear where they are located.

I called on air shocks for the tail dragger but was sorta laughed off the phone, appears to be no known application for a 89 420SEL. Running the air lines could be a bit tricky, coil around the shock and all. My old man threw a set on the back of his Caddy and pump them up when making a run over to the county line and they seemed to do the trick, beer n' liquor get heavy in mass quantities!

sixto · #4 08-30-2004, 11:41 PM

Block out some time and go through sections 40-300, -330 and -440 of the W126 shop manual. That should give you points of reference for determining what's not right. It was easier to sell the 91 300SE than figure out why it was listing

Sixto
95 S420
87 300SDL

GermanStar · #5 08-31-2004, 12:05 AM

Are you certain you installed the correct rear springs? Do you have the Benz part number of the springs you installed?

donbryce · #6 08-31-2004, 08:26 AM

Those rear springs are not under nearly the same tension as the front, so removal/replacement is not as dangerous using the right compressor. That said, I've used aftermarket rubber spacers on the tops of my rear springs in my streetrod, and those springs are out of the front end of a 77 450SEL. The coil diameter is almost the same as a late 70's Chev Nova.
I wouldn't consider those 'redneck' inserts that can be used to extend the spring because they make the spring act like it has 2 coils cut out (because the device locks the 2 together) and drastically affect ride quality as a result.
The rubber spacers are dirt cheap, fit great, easy to put in, and you can get away with leaving the stock rubber rings in there too if its necessary.

jim16671836 · #7 08-31-2004, 09:04 AM

I have messed with the 126 model from the later 80's that have the subframe rusted out where the shocks mount and even then the cars were not down in the rear end...You either have the wrong springs..length or spring rate is wrong...the only solution if you want to keep the springs is to install a new spring cup at the bottom. You can make the spring cans from pipe/tubing.. easy to do...just determine how much higher you want the car to ride and buy 2 pieces of pipe(length needs to be the amount you want to raise the car plus a couple inches longer for the spring to set down in) then weld a piece of 1/4 inch plate inside the pipe with a couple drain holes and then while the car is down apply compression springs and then jack up the body and install the spring cups by welding(disconnect the battery first) the new cups to the existing cups...IT WILL BE MUCH EASIER TO CHANGE THE SPRINGS...PULL ONE OF THE SPRINGS AND HAVE THE SPRING RATE CHECKED...

126nut · #8 08-31-2004, 09:28 AM

Thanks for all the reply's,

I am leaning towards the fact that maybe I have the wrong springs but I did get them at a reputable OE and aftermarket parts wholesaler who did some research with the VIN and all to make sure they were correct but who knows. The first set I got, one was OE and one was aftermrket, I was concerned with the compatability and exchanged them for two aftermarket springs, can't remember the name or part number, guess I need to do some digging. I think they were something like brembo?, bimbo?, I forget now,,,

Cigar Havana · #9 08-31-2004, 10:29 PM

I just replaced my springs. I got the MB springs, they actually have the MB logo stamped on them, also had 4 or 5 different colour brush marks. No sag, at all. Also replaced the rubber pads on top, but the old ones looked pretty good, and the tech. said they didn't need to be replaced, but I did it anyway. Those pads come in 3 or 4 thicknesses, so you have to get the right ones. Mine were about 3/4" in thickness, but I did not measure them so it is just a guess. I was warned that those worldpak springs just don't seem to be right for Fords, so there was no way I would trust them with a Merc, if they can't get a Ford right.

sixto · #10 09-01-2004, 03:42 AM

Quote:

Originally Posted by Cigar Havana

I was warned that those worldpak springs just don't seem to be right for Fords, so there was no way I would trust them with a Merc, if they can't get a Ford right.

Don't blame Worldpak. Even Ford can't get Fords right

Sixto
95 S420
87 300SDL
... we had a 77 Clubwagon when I was a kid; fabulous hauler but notorious lemon

86560SEL · #11 09-08-2004, 09:27 PM

Most all 86-91 S-Class sedans around here have sagging rear suspensions. I have a similar problem on my Lexus LS400. It does not have the air suspension (which was optional on these cars in 1990), but it will easliy sag if I have passengers, or even some groceries from the supermarket in the luggage compartment. Whats peculiar is that the car does not "sag" at all if nothing is in the back- something that some of the Mercedes do that I have seen. Even with about 150-200 lbs in the back, I can feel it occasionally "bottom out" on some bumps.

Not only my car- other Lexus owners have complained as well. Another automobile with this as a common problem is the 1984-2003 Toyota 4-Runner SUVs.

86560SEL · #12 12-11-2005, 12:13 AM

I know this post is kindof old, but since I have had bought a W126, I have noticed that my car seems to be "sagging" a bit in the rear as well. It does not bother me though. Is this too much out of the normal?

See photo:

420 SE · #13 12-11-2005, 12:25 AM

Hard to tell from that pic, one on level ground would be a lot better.

However, it doesn't really look to be sagging, but as I said, a level pic would be better.

Brian Carlton · #14 12-11-2005, 12:42 AM

Quote:

Originally Posted by 86560SEL

I know this post is kindof old, but since I have had bought a W126, I have noticed that my car seems to be "sagging" a bit in the rear as well. It does not bother me though. Is this too much out of the normal?

See photo:

I've made quite a few measurements of the body height relative to the camber of the rear wheels. The camber should be somewhere between -1/2 to -1 degree. So, the height of the body that corresponds to this camber is about 26" above the pavement. This is with 215-65-15 tires.

The SDL is currently at 27" off the pavement and the camber is below -1/2 degree. It also sits high in the back under all conditions other than full fuel and a heavy load of luggage. Then it's level.

But, the SDL currently has some custom springs that raise the body 1.5" above "stock". It's a bit high and I'll probably reduce it with thinner rubber spring pads. The current one's are at the max: 19 mm.

86560SEL · #15 12-11-2005, 01:27 AM

Thanks. Actually, where the car is parked is nearly level. Maybe slightly slanted, toward the lower passenger side, but very little. Here is another vantage point where it is more noticable that the actual car appears to be lower in the rear that the front. Scroll down toward the bottom for the "front" view.

Engine power on a 380SE ? Good? Also "coolant" level question

Quote:

Originally Posted by 420 SE

Hard to tell from that pic, one on level ground would be a lot better.

However, it doesn't really look to be sagging, but as I said, a level pic would be better.