Author Topic: Trailing arm mounts  (Read 1162 times)

Michael Foster

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Trailing arm mounts
« on: January 09, 2022, 13:38:03 »
Hello, I have been reading all the very valuable and useful information here, but I cannot find anything on my particular situation.

I am in the process of restoring my 1970 280 SL US specs. I have been at it for over 7 years and I am at the point where I am starting to put stuff back together. I have replaced all the floor as well as the mounts for the differential trailing arms. when mounting the trailing arms to their mounting bolts on the car floor I have found that they do not line up perfectly, there is about a 3/4" side to side offset between the rubber mounts and their mounting bolts on the car floor. I was able to pull the arms to the mounting bolts, but I do not think this is right.

I have measured from these mounting bolts to the front suspension carrier mounts, front back, left right and X, and everything seems to be good.

Is there any information on the car geometry and how to properly weld the trailing arm mounting bolts to the car floor?

M.Foster

mnahon

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Re: Trailing arm mounts
« Reply #1 on: January 09, 2022, 14:25:30 »
There's a drawing here that may be useful:
https://www.sl113.org/forums/index.php?topic=30013.msg217498#msg217498

For mounting the trailing arms, make sure you haven't accidentally swapped the right/left arms:
https://www.sl113.org/forums/index.php?topic=34009.msg249401#msg249401

Finally, there are a few threads that talk about installation of the arms and most of them do mention having to pull the arms into position, usually with ratchet straps:
https://www.sl113.org/forums/index.php?topic=13656.msg92797#msg92797

There's a tool that can help you line up the arm to the mounting point. There's a file to 3D print a version of that tool, but you'd need to be a full member to access it.
Meyer Nahon
Montreal, Canada
1968 MB 280SL Auto Euro LHD Silver
2021 Tesla Model 3

Michael Foster

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Re: Trailing arm mounts
« Reply #2 on: January 09, 2022, 15:35:24 »
Thank you for the information.

It seems that I may not be that far off. Any way I will check the precise location against the drawing.

Being under the car I have noticed that the rear springs do not sit squarely to the upper rubber spacers, there is about 1/4" space between the spring and the spacer on one side, although the lower fit fine??

M.Foster