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

Stretch · #1 12-05-2010, 01:49 PM

A desperate Sunday evening (well afternoon where most of you are) bump!

I'm not getting a warm wet feeling about this one... perhaps it isn't possible after all?

Billybob · #2 12-05-2010, 02:27 PM

Quote:

Originally Posted by Army

A desperate Sunday evening (well afternoon where most of you are) bump!

I'm not getting a warm wet feeling about this one... perhaps it isn't possible after all?

At the rear, outboard end of the swingarm there is a design difference described as "anti-squat", it can be found described in the 126 Body and Chassis FSM. I suspect that is the fundemental basic difference between the standard swing arm and the aluminum versions found on 126 coupes. How does this difference manifest itself as far as what will fit and what limitations on parts that connect are not known to me other than the differences exist. Good luck!

Stretch · #3 12-05-2010, 02:31 PM

Quote:

Originally Posted by Billybob

At the rear, outboard end of the swingarm there is a design difference described as "anti-squat", it can be found described in the 126 Body and Chassis FSM. I suspect that is the fundemental basic difference between the standard swing arm and the aluminum versions found on 126 coupes. How does this difference manifest itself as far as what will fit and what limitations on parts that connect are not known to me other than the differences exist. Good luck!

Yet again - thanks for your help Billybob - a good shove in the right direction. The seller won't ship the parts so as I've got to go and see them, I'll take a W123 trailing arm for comparison, a camera, and a tape measure. And in the meantime I'll leaf through the FSM. Cheers!

Stretch · #4 12-06-2010, 03:13 PM

Hmmm I thought I'd find more information on this. It seems to be common knowledge that the steel trailing arms are interchangeable... but I can't find much information about the aluminum versions.

I've read through chapter 35 in the W126 FSM and I can't make out for sure if the trailing arms with the anti-squat geometry were aluminum or not - I guess so...

It looks like I'll have to see these parts in the flesh.

To be continued...

rs899 · #5 12-07-2010, 01:00 PM

Did you try looking at part numbers in the EPC?

Stretch · #6 12-07-2010, 02:44 PM

Quote:

Originally Posted by rs899

Did you try looking at part numbers in the EPC?

Nope - I don't have it - I'll have a chat with the friendly dealer and see if he can help out.

JimFreeh · #7 12-07-2010, 06:30 PM

..... but I recall looking into this....

I recall the cast arms were titanium, and were issued on the 500 and 560 models. Diesels and smaller engined cars had the stamped steel like the W123. My 85 500SEL euro car had these cast arms, so I don't think they are exclusive to the 86 and up redesign.

From what I could see, it appeared the cast arms (forged?) were interchangeable with the stamped steel.

I also recall this may involve a change in the way the disk caliper mounts, but it certainly looked like the cast W126 arms would xfer to the W123, if the different parts were also changed over.

Jim