85 300d Front Shocks Replacement - PeachParts Mercedes-Benz Forum

tobybul · #1 05-23-2006, 10:16 PM

I just got my Bilsteins from Adsitco and installed one of the the front shocks. Its pretty easy especially if the 2 small bolts holding down the shocks at the lower end are not seized. I held off on the the other side till tomorrow after I sprayed the area with liquid wrench. The bolts wouldn't budge yet.

Anyway, my question is the correct placement of the big washers and rubber bushings that came with the shocks. It came with 2 washers and 2 bushings. The original on the car was one bushing and one washer. I am wondering in what order these go. The original on the car on the engine side (instead of wheel well side) from bottom to top was bushing, washer, bolts. on the wheel well side was just the shock boot - no washers or bushing.

I am not sure if the orig on the car is how MB did it since I have no reference to consult.

I have looked at some of the links provided in this forum but nothing specific to a 300D. Anyone know of a good reference or link? Thanks.

t walgamuth · #2 05-23-2006, 10:22 PM

i will speak from memory but i think all shocks are pretty much the same.

on the top of the shock should be an attached cup/washer. in that goes a rubber donut. this i pushed up under the hole in the fender. from the top you should have another donut then a washer/ cup then the nut on the top of the shock.

if you didnt have all these parts you may have some damaged parts in your car. look twice, sometimes the parts are stuck in the top of the shock and like to hide from you.

when you reinstall you want to squish the rubber down a bit.

good luck

tom w

olsaltybastard · #3 05-23-2006, 10:29 PM

You will need to use both that came with the shock. The other washer and bushing hides inside the dust cover. Take off the old dust covers and you will feel them. I installed both front shocks before discovering this. So, having done this twice in one night, I remember it rather well.

tobybul · #4 05-23-2006, 10:38 PM

Quote:

Originally Posted by olsaltybastard

You will need to use both that came with the shock. The other washer and bushing hides inside the dust cover. Take off the old dust covers and you will feel them. I installed both front shocks before discovering this. So, having done this twice in one night, I remember it rather well.

Looks like I'll be popping out the topside of the first one I put in. Ok, let me get this straight. The way it comes from MB is that the one set of washer and bushing goes inside the boot/dust cover. Washer first then bushing on top? Washer cup faced down or up? (I think face down).

On top side, bushing first then washer (I believe cup face up)

tobybul · #5 05-23-2006, 10:41 PM

Quote:

Originally Posted by olsaltybastard

You will need to use both that came with the shock. The other washer and bushing hides inside the dust cover. Take off the old dust covers and you will feel them. I installed both front shocks before discovering this. So, having done this twice in one night, I remember it rather well.

This actually makes sense. What made me wonder was after I got the one in (without the lower washer and bushing in place, the top shaft protruded to much on the top side. Now I realize it because the lower bushing/washer were not in place.

t walgamuth · #6 05-23-2006, 11:01 PM

are you sure about the lips?

dont those shocks have a picture with them?

tom w

Mercury · #7 05-23-2006, 11:28 PM

I had to check the shop manual. I have no ideal why it is this way. Both upper and lower washers go up. Picture is from manual. Hope it helps. There are more details of the assembly if you need them. You can get a cd of the shop manual from manualsunlimited.com for a reasonable fee.

phidauex · #8 05-24-2006, 01:05 AM

I did this install a while back, and posted some tips that you might find useful:

http://www.peachparts.com/shopforum/showthread.php?t=136306

This quote is the part that is most relevant to your current question:

Quote:

8: Slide the bump stop, then the dust cover, then a washer (cup facing up), and a rubber bushing (flat spot up) onto the shaft, and put the new shock tower in place. Don't worry about putting the shaft through the hole in the frame yet, focus on getting the lower bracket in place. Finger tighten the two bracket bolts, tipping the shock in and out on its pivot to allow better access, and turning the steering wheel from one side to the other to allow better access. I did the inner bolt first, then adjusted the wheel and shock position, and did the outer bolt second. Once these are both torqued down (you'll have to guess, I couldn't get my torque wrench in there, just snug them down as good as you can), compress the shock, and as it re-expands, guide the shaft through the hole in the frame. It will be tough to compress, but I only weigh 120 pounds, and I could do it, so you can too.

Double check that you have the bump stop, the rubber cover, the upward facing cup washer, and the rubber bushing (in that order) on the shaft before continuing. If you forget (like I did the first time), recompress the shock, and install those parts.

9: Once the shaft comes through the hole, install the other rubber bushing from the top (flat side down), then the other cup washer (cup facing down), and then the nylock nut. You may have to really press the washer down to compress the bushing a bit to get the nut to thread on. Give it a few good turns (don't crank it down), and move on. You may need to immobilize the shock shaft with a 7mm wrench on the flats shaft (at the very top) to prevent it from turning as you tighten the nut.

10: Once you have done both sides, reinstall your wheels (but don't torque the lug bolts down yet), and lower the car to the ground. Like all suspension components, you torque brackets and 'fixed' components while in the air (like our lower bracket), and torque flexible things like bushings with weight on the suspension.

With the car on the ground, you should torque your lug bolts to 90ft/pounds while you are thinking about it.

11: Now you can torque the nylock nut on the top of each shaft. Do NOT crank this down! Technically speaking, it should only be torqued to 19 ft/pounds, which is not much at all. You may not be able to use a torque wrench, because the shaft must be immobilized at the top with a wrench to tighten the nut, but just keep that number in mind. 19 ft/lbs is not much. What you should aim to do is get the nylon part of the nut fully on the threads, with maybe one or two threads exposed above it. The total exposed nut+shaft, above the washer, should be 24mm. If you crank this down too hard, you'll smush the bushings, and they won't do their job.

Important bits:

from the top down:

nut
washer (cup down)
bushing (flat side down)
body of car
bushing (flat side up)
washer (cup up)
dust cover
yellow bump stop
shock body

That is pulled right from the Bilstein manual. The nut is torqued to 19 ft/pounds. There should be 24mm of shaft + nut above the top washer.

Remember to do your final tightening AFTER lowering the car to the ground. Torque suspension components while they are loaded for best accuracy.

Enjoy your buttery smooth ride!

peace,
sam

tobybul · #9 05-24-2006, 06:59 AM

phidauex

I'm not disagreeing with you but I am wondering if the lower set of washer/bushing should be inside the boot/dust cover. Thats actually how I found the old one installed.

tobybul · #10 05-24-2006, 07:14 AM

Quote:

Originally Posted by Mercury

I had to check the shop manual. I have no ideal why it is this way. Both upper and lower washers go up. Picture is from manual. Hope it helps. There are more details of the assembly if you need them. You can get a cd of the shop manual from manualsunlimited.com for a reasonable fee.

I visited this site and seems you could bet a manual for lots of cars. Just does not say whether these are OEM manuals or what. Can you tell me since you have used it?

t walgamuth · #11 05-24-2006, 07:21 AM

well the lips away from the donut make a more compliant assembly. so for whatever reason they want the top to 'give' more than the bottom.

i think the dust cover does go over the donut. at least that is how i remember it.

tom w

phidauex · #12 05-24-2006, 10:32 AM

Quote:

Originally Posted by tobybul

phidauex

I'm not disagreeing with you but I am wondering if the lower set of washer/bushing should be inside the boot/dust cover. Thats actually how I found the old one installed.

Well, I've found things on my car set up in a lot of different ways, nearly none of them correct.

I'm no shock expert, but the order I listed was pulled directly from the installation sheet that came from Bilstein. I'm inclined to trust their judgement over any other, at this point. Though honestly, it probably doesn't make a lot of difference. My biggest concern with the boot inside the bushing is that you'd A) be protecting less shock, B) be subjecting the top surface of the boot to a lot of wear up against the body of the car, and it could fail at that point, and C) putting the foam bump stop right against the washer, potentially increasing its wear (though its not a really critical part, I admit).

Having the cups facing the bushing makes sense too, because it will help contain the bushings as they naturally start spreading. I know sometimes its helpful to turn the cup away for more compliancy (like on skateboard trucks), but I'm not convinced that this is one of those times, at least with the bushings supplied by Bilstein.

So anyway, I'm sure you've got some flexibility in how you install it, its not like the car will crash if the dust boot is in a different place, but the order I listed is straight from Bilstein, so if you deviate, make sure you've got a good reason for it.

peace,
sam

Mercury · #13 05-24-2006, 11:20 AM

Quote:

Originally Posted by tobybul

I visited this site and seems you could bet a manual for lots of cars. Just does not say whether these are OEM manuals or what. Can you tell me since you have used it?

It appears to be the real deal mercedes manual. The pictures are not of the highest quality, but the drawings are good. I'll send you the shock pages when I get home, you decide. It could be better with a search function. It does cover several years of all models.

Mercury · #14 05-24-2006, 11:24 AM

Quote:

Originally Posted by t walgamuth

well the lips away from the donut make a more compliant assembly. so for whatever reason they want the top to 'give' more than the bottom.

i think the dust cover does go over the donut. at least that is how i remember it.

tom w

Makes sense to have the rebound softer then the compression ? Love to hear from the bilstein folks on this.
Dust cover over the donut, protect the rubber from salt and other road spray.

tobybul · #15 05-24-2006, 12:32 PM

I'm not sure how old the shocks are on this car but I was betting they are the originals as they have MB's stamp on them. If so, then I'll have to trust thats how MB put it in. I only did one side so if the other side is the same, then I'll do it their way.

The old boot was in excellent condition - no tears or wear especially at the top where it contacts the body of the car. Also, I can't remember right now since I'm not home to check origs, but the Bilsteins came with a metal "cylinder" that slides into the foam stopper - about 3" long.

I can take pictures and post it on my note but don't know how to post it. Do I simply copy & paste?

On the side, I'm not sure anymore if the old shocks were bad because the compression seem to be the same as the new one when I pushed it down after I removed them from the car. The car does bounce at every corner when applying the bounce test.