I'm sure that this issue has been addressed previously, but I am currently attempting to replace a damaged right rear control/trailing arm assembly on a recently obtained 1985 MB 300D. I have absolutely no experience with independent rear suspensions, ergo, I'm seeking the wisdom of you guys.

I've seen that some say that a spring compressor is required while others say to drop the sub-frame. My question is, can I simply support the control/trailing arm underneath the spring with a floor jack, remove the two bushing bolts and lower the jack?

I ask because that's about where I'm at with the job. I've got the caliper off and the shock removed and planned to go about things as I'd mentioned but thought I'd better double check with someone who knows something...feel free to point and laugh.

Thank you. Any advice would be greatly appreciated.

Much of what you need is in this thread.

Replacing the Rear Shocks & Springs
http://www.peachparts.com/Wikka/W126RearShocksSprings

The sub-frame must come down to access the outer trailing arm bolts.
The parking brake cables must also be disconnected.






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1983 300D
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I haven`t worked on a SD like the Wiki above showes. But I have removed the complete sub frame, trailing arm, Differential and axles. Just did this job this past summer on my 85 300D. I removed it all to replace the bushings, and replace the trailing arms with lower milage ones because of a wheel bearing.

I have not replaced just one trailing arm by dropping down one side.
You can remove the REAR springs w/o a spring compressor.

Here is a link to a post I did to explain what I did.
Rear subframe removal and bushing replacement

Hope this helps, this is how I did a spring R&R w/o a compressor.

Once the shocks are removed, and the differential is unbolted (4 13mm bolts on diff mount.) then lower it downwith the floor jack, and the springs will just drop out.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

I had trouble getting the Nuts off of the Bolts the Trialing Arm Pivots on.
I had to use a Propane Torch and Penetrating Oil on them still had to use a lot of force.

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84 300D, 82 Volvo 244Gl Diesel

Wow...thanks a lot, guys. My experience is more on the NAS Land Rover side of things, again, feel free to point and laugh, so Mercedes + Diesel + Turbo = 1 lost whiteboy.

@whunter, thank you for the detailed and brilliant instructions. One question...the control arm is shattered at the spring seat and is separating at the hub/arm weld and am wondering if this is a symptom of something else or if this issue can cause other issues. I was sort of shocked to see this and am curious how to implement prevention and damage control.

Thanks again, fellas.

Trailing arm failure like this - shall we say - is not unheard of. Search though the forums and you'll see some great pictures. Rust is the main problem.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Oh...and I wish I had come here first. Trying to figure out the removal of the backseat almost had me resorting to a razor knife and I'm afraid the neighbor's kids may have picked up a new word or two courtesy of yours truly.

This MB runs great and is in excellent condition for something with over 200k on it but it does have several needs, as it should. I imagine I'll be frequenting this forum for advice and education...what a great asset!

Here is a couple links to some rusty Trailing Arms

rear trailing arm broke

IT FELL OFF! :)


Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

There were aluminum trailing arms available for the SD, weren't there, which didn't have the hollow interior to collect wet debris? I wonder if they have fared better in the long run?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I think that the aluminum ones are the ones used on "anti-squat" suspension - I'm slowly looking into this for a possible replacement on my W123. See:-

Trying to fit an aluminium W126 / 107 trailing arm to a W123 - a question of compatib

There are some good parts pictures even if you're not interested in the thread.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!