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Garage => Mechanicals => Topic started by: daantjie on 11 January 2021, 01:19 PM

Title: Trailing arm bushings - looks like "fun"
Post by: daantjie on 11 January 2021, 01:19 PM
Hi guys

Been putting this one off for a while, and of course kicking myself that I did not do this while I was working on flex disks, exhaust etc last year, argh...

My trailing arm bushings look crispy thus I have to assume they are original, oops.  But changing these out seems like a "fun" job as you essentially have to drop the whole rear subframe to get access, which of course means exhaust has to come off, as well as drive shaft unhooked etc.

Dropping and removing the whole subframe seems like a huge job, but I am guessing trying to fight these bloody things while the subframe is still attached to the car will be murder anyway?

Any one done this with some sage advice to share?  Looks like protecting the backing plates on the brakes is a must for starters.

Cheers
Title: Re: Trailing arm bushings - looks like "fun"
Post by: Max-NL on 11 January 2021, 02:00 PM
My dad and I did it on the 6.9 and my w123 230. It is a bit of a PITA job because like you said a lot of things have to be removed before you can drop the subframe. But you need to drop it because the trailing arms need to in an certain position before you can torque them (as mentioned in 35-110 in the handbook). But after you remove the exhaust, disconnect the handbrake, the driveshaft and the struts, removing the subframe is not that bad  ::) . I'd suggest supporting the subframe under the diff and the 2 mounting points when you're loostening/removing the bolts.

If you have access to a lift than great, but if not it's doable on the ground as long as the rear is high enough for clearance.
Title: Re: Trailing arm bushings - looks like "fun"
Post by: daantjie on 11 January 2021, 02:17 PM
Quote from: Max-NL on 11 January 2021, 02:00 PM
My dad and I did it on the 6.9 and my w123 230. It is a bit of a PITA job because like you said a lot of things have to be removed before you can drop the subframe. But you need to drop it because the trailing arms need to in an certain position before you can torque them (as mentioned in 35-110 in the handbook). But after you remove the exhaust, disconnect the handbrake, the driveshaft and the struts, removing the subframe is not that bad  ::) . I'd suggest supporting the subframe under the diff and the 2 mounting points when you're loostening/removing the bolts.

If you have access to a lift than great, but if not it's doable on the ground as long as the rear is high enough for clearance.

Thanks good tips.  I think I need to leave this jobby for the summer so I have lots of warm weather and time on my hands ;D
Title: Re: Trailing arm bushings - looks like "fun"
Post by: Alec300SD on 11 January 2021, 02:20 PM
I am in the process of re-doing the rear suspension on my 1979 300SD.
For the rear trailing arms, here is a link to a great DIY pictorial at the 500Eboard forum:
https://www.500eboard.co/forums/threads/how-to-rebuild-late-w126-rear-trailing-arms-including-rear-wheel-bearings.13784/


The rear subframe needs to be dropped to access the rear trailing arm bolts.
I am upgrading to KMAC bushings (# 501826 I) to allow for adjustment of rear camber and rear toe.
Title: Re: Trailing arm bushings - looks like "fun"
Post by: rumb on 11 January 2021, 02:34 PM
That is an excellent tutorial! 

All bearing can be purchased by brand name instead of thru MB for a substantial discount.

the 6.9 is even more work due to the anti squat mechanism.

All the seals, bearings and shells were very hard to remove.
Title: Re: Trailing arm bushings - looks like "fun"
Post by: daantjie on 11 January 2021, 03:02 PM
Absolutely, thanks for the link.  The guys on the 500e board take things to the next level, very professional and no BS approach 8)