Author Topic: Trailing Arm Mysteries  (Read 6693 times)

jcochran@cox.net

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Trailing Arm Mysteries
« on: November 30, 2014, 05:33:54 »
Hi,
 I recently had my mechanic replace the bushings in the differential trailing arms on my 1967 250SL because the bushings where the trailing arms attached to the differential were disfigured and apparently misaligned although they seemed to have been in service for many years. After replacing the bushings it was noted that the car stood "high" in the rear and the new bushings were distorted in a similar fashion to the old ones. The car has never been wrecked but the arms seem to be under undue pressure from the coil springs in that they tend to want to rotate opposite of the axle. That is to say that viewed from the rear of the car the left arm is rotated counterclockwise and the right arm is rotated counter-clockwise. I like the way the car looks with the rear-end a little high (I am the second owner and it has always been that way) but the new bushings are obviously under duress. Any help on this matter is greatly appreciated (wrong shocks, coil springs, compensating spring, etc.).

Thanks,
Jim Cochran

ja17

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Re: Trailing Arm Mysteries
« Reply #1 on: November 30, 2014, 06:12:25 »
Hi Jim,

By chance have you checked the main rubber mount in the trunk?
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

GGR

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Re: Trailing Arm Mysteries
« Reply #2 on: November 30, 2014, 10:47:28 »
Also these arms have a side. I wonder what happens when they are interverted by mistake.

Naj ✝︎

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Re: Trailing Arm Mysteries
« Reply #3 on: November 30, 2014, 12:50:34 »
These arms are handed as GGR suggested.

You can distinguish by the extra 1/2 moon plates spot welded where the front bushes go.

Naj
68 280SL

ja17

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Re: Trailing Arm Mysteries
« Reply #4 on: November 30, 2014, 15:56:07 »
The as mentioned are right and left. When installed correctly they angle inward slightly.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

jcochran@cox.net

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Re: Trailing Arm Mysteries
« Reply #5 on: December 01, 2014, 01:35:41 »
I had all of the bushings replaced except for the "clunk" bushing on the differential which will be replaced at a later date. Judging by the pictures the trailing arms on my car have been reversed since I purchased it as my restorer's re-installed them the way they came off. I am assuming that "R" is the passenger side and "L" is the driver side of the car. I have forwarded the picture to them and I'm hopeful that this will solve the issue.

Thanks you all so much for your help,
Jim Cochran

JamesL

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Re: Trailing Arm Mysteries
« Reply #6 on: December 01, 2014, 14:24:46 »
No
R would be drivers side
L would be passenger side

But then I sit on the right when driving  ;D (so yes, for a LHD car, you would be correct!)
James L
Oct69 RHD 280 in DB906 with cognac leather

jcochran@cox.net

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Re: Trailing Arm Mysteries
« Reply #7 on: December 07, 2014, 03:37:42 »
We installed trailing arms from a 280SL and the bushings looked much better so I am trying to procure a pair. Does anyone know if these are still available and if so who has them?

Thanks,
Jim Cochran

ja17

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Re: Trailing Arm Mysteries
« Reply #8 on: December 07, 2014, 03:41:37 »
Hello Jim,

There should be plenty of good ones available. I think they are on the same on many other models of the era.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

jcochran@cox.net

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Re: Trailing Arm Mysteries
« Reply #9 on: December 07, 2014, 05:07:35 »
They are the same but I'd like to find a vendor in the USA who sold the originals or a very high quality reproduction. I have been searching but it doesn't look good.

Thanks,
Jim

ctaylor738

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Re: Trailing Arm Mysteries
« Reply #10 on: December 07, 2014, 17:49:38 »
According to the EPC and the price list, they are still available from Mercedes.  PNs 110 350 10 29 and 11 29.  A bit pricey at $1120 list each.
Chuck Taylor
1963 230SL #00133
1970 280SL #13027 (restored and sold)
1966 230SL #15274 (sold)
1970 280SL #14076 (sold)
Falls Church VA

ja17

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Re: Trailing Arm Mysteries
« Reply #11 on: December 08, 2014, 05:36:30 »
Find good used ones out there for $100.00 or less each.  I am sure there are plenty of group members that have an old rear diff laying around from a conversion.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback