I had my '85 300D in for an alignment recently and the tech said he was having trouble bringing the rear fully into alignment due to rusty trailing arms that he thought might be bent. He recommended replacement of the trailing arms.

I was aware of the trailing arms being a bit rusty, but does it ring true that they might be bent?

Here's a pic of the right trailing arm rust, does this pose an imminent danger or a likelihood of being bent?





My car does seem to be sagging in the rear a bit, and when looking at it from the rear the tops of the rear tires lean inward ever so slightly. However I've thought this could be due to:

• A few years back I cut half a rung out of the rear springs and swapped in the thinnest spring pads. I did this after rebuilding my front suspension and used KMAC springs in the front which sat a bit lower. At the time the rear seems to sit up to high.
• AFAIK the rear bushings have never been done (car has 310k), so at the least I probably need new subframe bushings and differential mount bushing

I guess my question here is whether the trailing arm(s) really need replacement due to rust, or am I ok to just add subframe bushings, new springs/spring pads, etc... to try to improve the rear alignment?

Change it immediately - the chances are pretty big that it is a lot worse on the inside.

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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!

And I'm surprised the tech at the alignment place managed to make adjustments on the rear wheels on this system as you need to remove the trailing arms and put in eccentric bushings - so if he really said he made an adjustment I'd like to know if he was once an understudy for Uri Geller...

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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!

X2!!!!!!!!!!!!!!!!!! DO NOT drive on that anymore, its an accident waiting to happen....

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2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

Yup... find a better one. The uni body design of it doesn't cope well with rust.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Yeah you better just part the car for a while till you replace the arm or both arms.
They are just two pieces of stamped sheet metal welded together.
It`s not the rust you see, but what lurks inside.
You may get 500 miles or 5 miles before it suddenly becomes a danger to you and every one around you.

It can lead to this.


Or this
Rear Left Trailing Arm Has Cancer - Mercedes-Benz Forum


Charlie

sent from my pos computer

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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

Naaaah, that'll buff out.....

just kidding.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Charlie means, "PARK the car" not "PART the car" I believe. Of course I could be wrong and he is looking for some parts for his ride.

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
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Yes those trailing arms or at least one is very,very weak I think. I would inspect the whole lower chassis for any other problamatic areas as well.

Hope it is only the trailing arms and may just be. I would not drive on them either.

Well, that was a unanimous round of responses. Looks like I will be replacing my trailing arm(s).

The rest of the car's underside looks good. My axle boots are worn but not cracked yet. I live in Seattle, but I bought the car from Nebraska and I believe it was previously somewhere on the east coast.

Anyone have some good trailing arms for sale

Also, would it be easier to just drop the entire sub-frame and replace while off the car, or swap them out one side at a time? I'm leaning toward the former since I need to do the sub-frame bushings and other bushings and possibly the axles as well. On the other hand if it is as dire as it sounds maybe I should swap in a new arm asap and work on the bushings and other replacements at a later date.

Once she's up on stands it's not too terrible with a big breaker bar. Make sure it's on level ground before you start

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$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

Sorry, do you mean for swapping in a new arm without removing the subframe, or dropping the entire subframe and replacing with the subframe off the car?

I replaced a trailing arm for same reason, '85 wagon, and my car had lived in the rust belt too long so the job was very tough. I had access to a very nice lift for that job, and also a "blue wrench" aka oxy-acetelene torch, and it was two hard days of work, 8 hours each day. In my case I did what you're thinking about, I did ALL the rubber while I had the rear end apart. I also replaced both supply and return fuel lines, as one of those was rusted and starting to weep.

If your car is not too rusty, and you've got prior experience with pulling out and pushing in new bushings, I'd plan on one long day of work.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

As a voice of dissent, my 240D had a 3" crack near the axle end of trailing arm when I bought it in 2007, and I had a friend weld it to repair it in 2014, because the edges were rusting. I'd check it with a hammer or screwdriver and see how much material has rusted away and where. Why not weld or braze a patch on?

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CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

It'd be a tricky patch since the shape of the damaged metal is a double curve, and it is thin metal so it requires the correct equipment and a skilled welder. Finally with the inside not visible it is hard to tell how much of the part is damaged inside where it is invisible.

But yes, if you could find the right person a patch would work.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.