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Discussion Starter #1
Long time reader, first time poster! Hope you guys can help please :smile

As titled I have a 98' S420 W140 without SLS, and the rear suspension runs too low.

As you might be able to see from the (random, crappy) pictures, the rear has about 1" of clearance between the arch and top of the tyre wall. A couple of MB specialists in the UK, PCS, WGMB and Starwerx, have seen the car and agree the rear runs too low.



The car runs a LPG kit with a small, 40l toroidal spare wheel well tank. I suspect this extra weight is contributing to the issue. With rear passengers the car will frequently bottom out over bumps and undulations.

So far I have changed the rear dampers and springs to Bilstein OEM spec which hasn't helped the ride hight. I refreshed the rear tired stock suspension using the following parts:

BLS24-017077 (Bilstein B4 Gas Shock Rear Absorber)
BLS36-129577 (Bilstein B3 Original Equipment Rear Spring)
Also added in the thickest shim (4 notches IIRC).



I've changed the front too (which remains at a normal height), and the comfort and handling have both really improved. However the rear ride hight is exactly the same! :banghead:



I'm hoping to rectify the sag with some firmer / taller springs. Looking at the MBOC EPC, there are two spring options, the firmer option for cars with lots of OE equipment (rear elec seats, fridge etc) is A1403242104 AFAIK. I don't want to buy these OEM springs from MB because of the cost coupled with the fact that they might not resolve the issue. I also don't have the original springs for part number reference.

What I have seen is both, Lesjofors and Kilen sell a "reinforced" spring for the W140. It doesn't give any further info, just says, "for vehicles without leveling control - Reinforced Version". I'd go for these straight away, they're cheap, but their OEM equivalent number doesn't match anything I've seen in the EPC for my car.

The OEM equivalent number for the Lesjofors reinforced spring is A1403241404. I'm not an EPC pro and haven't managed to reference this number against my car, so I don't know if they will fit / fix the problem? :confused:

Long shot - but can anyone shed some light on the Lesjofors spring compatibility or recommend a solution?

Cheers! :grin
 

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Welcome to BW

Sagging with new springs and new thicker shims is probably a good indicator that something with the parts is amiss.

If you have done your research (and it is clear from your post that you have) and the rear is still sitting low, I agree -- you need the uprated springs.

Good luck,
Steve

PS While I was doing the suspension work on my C140 this past winter, there was a short period of time when the car was on the ground, supported by the springs only (both SLS absorbers were out) and my rear was not sagging too badly. It had almost no gas in the tank, but on the flip side, the springs for the SLS system should be much softer and w/o the shock absorbers, the rear support should have been much compromised....
 

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Discussion Starter #3
Thanks, Steve. It is a possibility that the Bilstein springs, although the correct P/N, are the wrong spec for the car.

It's good to know your springs, even without the dampers, are still supporting the car properly. It must be the Bilstein springs. However, the OE springs I replaced had exactly the same problem. Hmmm...
 

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Discussion Starter #4
The LESJOFORS SPRING number you gave appears to be for heavy duty rear springs pre 95 which seems to be a break point before /after for springs for these cars. Would not perhaps be applicable your car being a 98? Really depends on if the change affected fit or spring rate [ the w140 supposedly lost weight after its facelift]
I've been given this information. Does anyone know if pre 95 springs will fit a post 95 W140? It could be worth a try! :)
 

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... about 1" of clearance between the arch and top of the tyre wall ...

That's roughly where my S420 runs with factory rims & tires. Only ever had the shocks changed. It's never rubbed and I've loaded up the trunk beyond a gas tank etc.

What is your tires size and wheel offset?
 

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That's roughly where my S420 runs with factory rims & tires. Only ever had the shocks changed. It's never rubbed and I've loaded up the trunk beyond a gas tank etc.

What is your tires size and wheel offset?
Joe:
The OP-er attached this picture in another thread:



This is nearly a frontal view and I think I can tell from the photo that the rear has sank quite a bit.


Offset and tire size are secondary to the question why the rear suspension is not letting the car take some load (from the picture it appears that the wheels are NOT w140-spec and the offset is on the "aggressive" side, possibly in the 30s).

Best regards,
Steve
 

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Yeah if the offset is out, it will compress the rear noticeably more. I noticed this when I put spacers on the rear of mine. I'm guessing he has a full trunk load in that pic too? Maybe full tank of fuel as well? Gas tank in the spare wheel well is weight quite a way back from the rear axle, explains the lift in the front too.

I think with the gas system where it is and the low offset combined is causing the compression. Low offset wheels causing it to rub.

W140 has a long travelling suspension with a low spring rate. Differences in weight make a large difference in height vs normal cars, hence the SLS system.

I'd personally look at moving the gas system as close to the rear axle as possible for better weight distribution, put factory W140 wheels on with correct offset (for proper weight rating too) and lower the front.
 

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Hello All,

yojay, I have the same problem with W140 420 '97 (grey 744 too) with LPG.
Last year I've changed the spring. I used LESJOFORS with 4 dots rubber . Car looked exactly like yours.

2 weeks ago I changed the springs to the original from MB.
Car has the same problem : too low, too soft.
MB Dealer checked the springs number in German. For them (from the office point of view) springs are correctly ordered.

Did you solve the problem with rear springs?

BR,
ux
 

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I have the same springs Bilstein B3 and the same shock absorbers Bilstein B4, but i feel the car very stiff, i feel every bump.
Is your car the same?
 

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My W140 has too low and too soft springs (original MB).
It's possible there is a problem with MB springs calculator.
I'm waiting for the response from MB dealer.
 

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Hello All,

yojay, I have the same problem with W140 420 '97 (grey 744 too) with LPG.
Last year I've changed the spring. I used LESJOFORS with 4 dots rubber . Car looked exactly like yours.

2 weeks ago I changed the springs to the original from MB.
Car has the same problem : too low, too soft.
MB Dealer checked the springs number in German. For them (from the office point of view) springs are correctly ordered.

Did you solve the problem with rear springs?

BR,
ux
You need to offset or compensate for the LPG system weight.
 

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Discussion Starter #15
Hi folks, my car is still running at the same ride height at the moment. I've picked up some new front springs as I suspect the current front springs (fitted new by the previous owner) are too tall for the car. This would contribute to lifting the front of the car and compressing the back. I have not bought new rear springs as yet.

In regards to ride quality on the Bilstein dampers I fitted, it is perfect! Very cushy and comfortable but also well damped so the car does not bounce up and down after an impact.
 

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Hi All,

Problem solved, finally!

I bought LESJOFORS Springs 4256869 - version HD. Officially only for W140 before lift.
I had to replace upper rubber 1403210684.

2604862


One issue to notice:
Springs are bigger than originals with very small place to the other parts.
After > 200km no problem but I have to inform about that.

Have a nice weekend,
 

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Discussion Starter #18
Hi All,

Problem solved, finally!

I bought LESJOFORS Springs 4256869 - version HD. Officially only for W140 before lift.
I had to replace upper rubber 1403210684.

View attachment 2604862

One issue to notice:
Springs are bigger than originals with very small place to the other parts.
After > 200km no problem but I have to inform about that.

Have a nice weekend,
Thanks for the post and pic! Very useful. I’ll give this a try too. I might adjust the spring pad thickness to perfect the ride height along with the HD spring.
 
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