W124 Rear arms and struts - PeachParts Mercedes-Benz Forum

Chris W. · #1 07-31-2003, 04:05 PM

I just bought the full kit of 4 links (tie rod, support arm, camber strut, and support arm) (not the shocks) per side from Phil for the rear of my 95 E300D. And not the subframe mounts.

I am planning on doing this job this weekend. My question is, do I need to have the rear suspension loaded when I tighten the bolts? I think I remember reading this somewhere.

I was planning on replacing all the links on one side but keeping them loose, then doing the other side, then putting some blocks down, put the wheels back on, set the car down on the tires but elevated on blocks so I can get under there, and tightening everything up.

Do I have to go to this trouble, or can I just tighten everything with one side jacked up and wheel removed, with suspension hanging and then do the other side?

(and yes, I have and use excellent jack stands!)

TIA,
Chris W.

sbourg · #2 07-31-2003, 05:27 PM

If you do not load the suspension, the bushings will wear out prematurely. However, unless you can adjust rear toe to spec, you will need an alignment anyway, and could ask the tech to do it on the rack.

There are five links, though, and I am not familiar with the names you used. Are you replacing the pivots in the spring support arm?

Steve

Chris W. · #3 07-31-2003, 10:24 PM

That's an interesting question. There was a thread which identified the particular arms as follows, with the MB name first and the Fastlane name following:

1. Thrust arm ---------------------> Thrust arm
2. Tie rod -------------------------> Control arm strut
3. Torque strut -------------------> Control Arm Stay
4. Camber strut ------------------> Camber strut
4. Spring Link ---------------------> Sway bar link

However the names and part numbers on the Fastlane ticket are as follows:

Tie rod ...............210-350-2153 (2753?)
Support Arm...... 210-350-3306
Camber Strut......210-350-3406
Support Arm.......210-350-3806

The tie rod part has one number on the plastic bag (210-350-2753) but has 210-350-2153 on the box enclosing the bag!

I did not get the sway bar link arm.

Here is a pic, with the 4 arms, I can only identify 2 of them. Maybe someone can ID all of them.

I think I'll wait until I do the front end before I get a 4 wheel alignment.

Rgds,
Chris W.

bobbyv · #4 07-31-2003, 10:57 PM

the longer of the 2 unknown linkages is the "Thrust arm"; in the (190e) Haynes manual, it is referred to as the "Pushing Strut". I believe it is so called because it transmits the forces that propel the car forward.

the shorter one is the "Torque strut"; this is referred to as the "Pulling Strut" in the Haynes manual. I believe it is called a "Torque strut" because it converts the braking torque into an anti-lift action on the rear suspension.

haasman · #5 07-31-2003, 11:09 PM

Question: Do the new 124 rear links also get the different bolt and bushing as the 201 models? If so you might need to check with the dealer.

In essence, if true, the bolt holes on some of the links are larger and require a different setup including a star socket.

Haasman

carman850 · #6 07-31-2003, 11:10 PM

Quote:

4. Spring Link ---------------------> Sway bar link

That is not correct, spring Link is actually the lower control arm, it is the biggest of 5 links, Sway bar link is not one of the 5 links.

5 links are: Torque strut, tie rod, camber strut, thrust arm and lower control arm(MB calls it Spring link)

hs_300e · #7 08-01-2003, 12:09 AM

If your car needs the newer bolts, the number for the bolt kit is 210 350 45 06 and that for the bushing is 210 352 00 43.

In all you will need three sets of the bolt kit per side and 3 sleeves/bushings per side. The bushings go into the carrier. When I replaced the links on my '86 300E, I used the new longer bolts from the bolt kit along with the bushing where the thrust arm, camber strut and torque strut connect to the rear wheel carrier. I used the old bolts where the above three links connect to the chassis because the old bolts had the hex head and it was easier to use a socket on them. The new bolts need a torx bit.

The rear axle shaft has to be horizontal before you torque down all the links to the carrier and the frame. If you have the MB service manual, the files to refer in the chassis section are:

35-110.pdf - for the camber strut
35-111.pdf - for the torque strut
35-112.pdf - for the tie rod
35-113.pdf - for the thrust arm

Make sure the vehicle and the rear axle are supported well and use exterme caution when torquing the link down.

Good luck and let us know how it goes.

Chris W. · #8 08-01-2003, 08:29 AM

Just a nit to pick. The new bolts are not Torx. They are sometimes called "triple square". I just spent yesterday lunch hour looking for a socket bit to fit. Others have mentioned that they found one at Sears, but I could not. I found a "metric internal" wrench at NAPA (12mm) and Pep Boys had a Lisle kit with that and 3 other sizes.

I'm still not sure what the official name is. And the ones I found are not socket bits - they are just a 1/2" hex shaft with the 12 mm fluted end. You can stick the "bit" into a 1/2" socket. I'm concerned about fitting that combo on all the bolts, so I'd still like to find a true socket bit. Gotta flag down a Snap On truck or something...

Chris W.

md21722 · #9 08-01-2003, 10:13 AM

Chris,

- You will need new SLEEEVES (3 per side) for this project as well.
- The axle should be horizontal.
- The bolts are XZN or triple square. I used a bit from AutoZone and also one from Stahlwille. They are a TIGHT fit and you will need to be creative. Its really much easier with the entire subframe out of the car but that's a whole other story

csnow · #10 08-01-2003, 12:46 PM

I wonder...

Is it actually easier to just bite the bullet and remove the entire subframe if you are doing extensive repairs?

Chris W. · #11 08-01-2003, 12:58 PM

That is a good question. I was planning to do the links and arms myself and take the car to a shop for the subframe bushings and diff mounts.

Do you think I should just bite the bullet and have the shop pull the whole subframe, do the links and everything at once?

I hate the idea of having to take off the exhaust, brake lines, drive shaft, etc.

Chris W.

csnow · #12 08-01-2003, 01:21 PM

Right. Exactly what I was thinking.

Seems like wanting new subframe/diff bushings along with everything else might tip the balance towards removal.

Opinions?

psfred · #13 08-01-2003, 07:47 PM

I plan to do the whole shebang on the 300D this fall when I have (hopefully) more money. I did a torque link and a thrust link on the passenger side, but need to do diff mounts, subframe mounts, and the rest of the links look iffy, too. Probably going to pull the springs and do the bushings in the spring link, too.

You must use a jack to lift the suspension to near normal height to tighten the links. The steel sleeve is held tight by the bolt and does not rotate, so if you tighten with the suspension haning, the rubber will be overstressed and fail rapidly. Don't know how fast, but this is such a PITA I'm not taking any chances.

No way you are ever going to tighten the bolts with the wheels on, let alone sitting on the ground -- it's almost impossible to get to the inner ends with the wheel off! One of th reasons I'm going to pull the subframe -- I can do final tightening in place, but I will be able to use power tools rather than unscrewing a nut one flat at a time for 1/4" of fine thread!

Peter