Coil/Spring Shim (Warning sort of) - PeachParts Mercedes-Benz Forum

Manual Life · #1 11-03-2010, 09:37 PM

A warning. I know it will be a rare event when someone does what I did but I figure I will offer a warning in the case that someone does do what I did. (Feel free to refute my claim)

Some time back I decided to raise the rear end of my 300D by adding larger coil/spring shims in the rear. The result was unfavorable as I believe the higher angle of the differential to the hub assembly was too much increased and and put too much strain on the cv-axle boots. (old boots in moderate condition, and no i did not tear them durning the shim removal and replace process) As a result the boots tore, both in exactly the same location and at about the same time.

I added the 19mm from stock. And am now back to stock.

Why did I do this in the first place? I wanted to look at less of the hood.

charmalu · #2 11-04-2010, 03:01 AM

The rear shims come in three sizes as listed in All Parts Express. 9.5, 14 & 19mm. not sure which one is the stock size, but if 19mm is listed as one for the 300D, really don`t see how it could rip the CV boots.

Your boots might have been already cracked, and just a coincidence they gave out.

If you have ever seen your car up on a lift, or jacked it up by the differential, the axles are at a greater angle than the shims could have caused.

Charlie

Stretch · #3 11-04-2010, 03:50 AM

I'd go along with what Charlie says - but I guess the way to check for sure would be to measure the position of the trailing arms and compare that with the specifications in the FSM.

Have a look at post 4 in this thread:-

How I adjusted the toe in / out, camber and caster on my W123 300D

(Sorry to here of the demise of your cv boots btw)

vstech · #4 11-04-2010, 09:49 AM

a better way to get angle for the hood, is to lower the front.

I don't see 19mm lift causing boots to tear, but if they were already at the point of failure, any change would split them. it's amazing how brittle the boots get when cracks are present.

if you need boots, or axles I can help. lemme know!

cirrusman · #5 11-04-2010, 09:55 AM

You could just borrow someone's 80s Cadillac and drive it for a month, then go back to the Benz and voilá, your hood looks tiny!

Manual Life · #6 11-04-2010, 10:32 AM

ok, i'll take it that it wan't the shims.

i didn't do the front springs because they are scary without the mercedes tool and I don't have the mercedes tool.

cadillac, that would cure my hood issues.

vstech · #7 11-04-2010, 10:54 AM

ebay has the knockoff mercedes tool for under 200 now. I got mine for 179. I've not used it yet, but I'm hankoring to slap it on once the car is up in the shop!

ColLonewolf · #8 11-04-2010, 11:31 AM

Is there any way to tell what shims are on the car without taking them out?

babymog · #9 11-04-2010, 12:15 PM

The spring pads have bumps on the edge of the rubber, which correlate to the rubber pad thickness. I believe that 4 bump is the thickest.

charmalu · #10 11-04-2010, 01:47 PM

{Why did I do this in the first place? I wanted to look at less of the hood.}

HMMMM, that is one of the reasons I love the Mercedes, that long flat hood. Both the 123 and 126.

Almost all new cars, the hood drops right off, and all you can see is the bottom of the windshield, and then nothing.
The new trucks are like that also, nothing like driving a Peterbilt or Kenworth and having 12 ft of hood out in front.

When we first got the 123 and saw that flat hood out front, I thought, WOW!!!! A real car.

Reminds me of that old song, with some of the words "Big Loooooong Cadillac, Tailor mades upon my back.............etc....

http://www.youtube.com/watch?v=gZutNGdcqH0

I think it would be hard to make the hood disappear. start lowering the front end too much, and have to think of the oil pan hitting something.

I installed 240D front springs, it did lower it some. I did this because of the 4-spd swap, the automatic being heavier and the 4-spd lighter, the front end came up quite a bit. rides good, just a little soft in the corners. I have a TD sway bar to install to stiffen it up. Iam using the 1 nub pads.

Here is a pic of the nubs on the edge of the pad.

Charlie

JB3 · #11 11-04-2010, 02:10 PM

to reiterate the above posts about the half shafts. Changing the ride height or angle of the axle with a 30 year old boot which has become set in its ways definitely causes the rubber the crack and eventually leak. Ive done this both ways, overloading the trunk on a sedan, and doing exactly the same thing you did, trying to raise up the back end.

My reason was for towing, I put in new springs, heavy duty shocks, and the thickest spring pads I could find, with the result that in less than 5 thousand miles both boots on both axles cracked and leaked. I replaced them and it was fine for the rest of the time I owned that car, another 30-40 thousand miles.

You just needed some fresh rubber on those axles. This is really a warning though as you say, not because its a bad idea to change the ride height, just because it will cause failure of already ailing or old components, all you've done is given it its excuse to break.

Kind of like kicking the walker away from grandma and waiting for her to fall on her own.

cirrusman · #12 11-04-2010, 02:15 PM

Quote:

Originally Posted by charmalu

Almost all new cars, the hood drops right off, and all you can see is the bottom of the windshield, and then nothing.

Charlie

True true. I like being able to see my hood. In the Caddy, all 10 ft of it

charmalu · #13 11-04-2010, 11:49 PM

Just normal driving, the trailing arms go up and down with the humps, bumps, dips, speed bumps, drive ways etc... a lot more than a few milimeters the springs pad would change.

we just came back from a short trip. had the car loaded down with luggage etc.... and my 5000# tool box

, and she was squatted down pretty good.

we need a poll, long hoods vs short hoods, or no see hoods

.

Charlie

vstech · #14 11-05-2010, 12:53 AM

I think what's being said, is that on an old car with original boots, if you plan on intentionally changing the ride height, inspect the axle boots as well. replace the boots if they are cracked and aging. or they will fail quickly.

Ndralle · #15 07-12-2013, 04:01 PM

i know this is an old thread butt.....

to prevent this could you also lower the rear differential mount. that way the angle of the cv axles would be the same?

would this also correct the camber issues?

would you need to do a full body lift to correct camber issues?