I have a terribly rusted out passenger side travel arm. Its so bad the wheel is now flared outwards. The car is just plain unsafe. Here it is:


I do not drive on a regular basis so I can afford to have the car on jackstands for days at a time, hence I want to undergo the repair process myself
I already have a replacement travel arm from a junked car, just need some more clarification on the install process.



Mark DiSilvestro was kind enough to provide this good post:

However, I'm just still not grasping the full process. Are there any pictures of the process? I may sound like a simpleton but I'm just a very visual learner and reading the procedure sometimes doesn't do it for me.
Any further detail to the process would be much much appreciated as well

__________________
-Dan
1983 240D AT, 163K running on VO, "The Patience Tester"

Bump

__________________
-Dan
1983 240D AT, 163K running on VO, "The Patience Tester"

The post is accurate.

What don't you grasp?

I'm just trying to visualize this process


Is the goal to angle the cars rear end so the side with the bad arm is pointing to the ground?

The instructions don't seem to mention how to undo the disc rotor and everything from the axel. Is it straightforward?

I've just never done any work like this and don't know what to expect and without pictures I'm still left wondering.
I'm at the point where I'm just going to go and give it a shot but I wanted to just try to see if anyone had any more valuable information to contribute

__________________
-Dan
1983 240D AT, 163K running on VO, "The Patience Tester"

Call me Monday.



Have a great day.

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1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

There is no requirement to "angle the car's rear end". You block it up in the traditional manner on the body.

The disc is removed via the use of a large rubber mallet to break it free from the hub. If they get very difficult, a bit of heat is preferred.

It's a lengthy and time consuming job and is really not suited for a beginner. We can talk you through it, but, be prepared for quite a few obstacles along the way. Patience will be a virtue.

Hopefully, the condition of the bearings and hub in the new trailing arm is satisfactory. You certainly don't want to replace bearings in that unit.

I didn't take any detailed photos, and have no way to post them anyway.

Are you getting a complete used trailing-arm & hub assembly? In my case the trailing arm came with a rotor, but the salvage-yard had cut the emergency brake cable, so I had to pull the rotor anyway, and transfer the original cable from my old trailing-arm. I decided to re-install my original rotor to the used replacement trailing-arm, and and keep the used rotor as a spare.

Fortunately, the used arm's bushings and hub-bearing were in good shape, so I didn't have to struggle with their replacement.

Once the caliper is unbolted, the rotor may just come off the hub or you may have to persuade it with a mallet.

One of the more trying and dirty parts of the job was unhooking my original emergency-brake cable & it's sleeve from under the car, and transferring it to my used replacement trailing-arm. Struggling with the tiny emergency-brake shoes, springs, adjuster & linkage behind the wheel-hub flange, in order to swap cables was most aggravating!

Once the center-bolt was removed from the hub, the outer axle-joint came loose fairly easily, though I may have had to tap on it slightly.

After I placed a jack under my broken trailing-arm, and unbolted it's shock and stabilizer link, I simply let that arm swing down till it contacted the stop on the crossmember, and could swing no further. Then I moved the jack under the differential and placed a second jack under the end of the crossmember.
The point is not neccessarily to have the 'rear-end' pointing at the ground, but to lower the differential and the one end of the crossmember JUST ENOUGH so the outer trailing-arm bushing-bolt clears the body, and NOT SO FAR that the other crossmember bolt and driveshaft connection is overstressed.

You can't remove or install the outer trailing-arm bolt until that end of the crossmember is lowered clear of the body - about 3 inches. And you can't lower that end of the crossmember far enough, without also unbolting the differential mount from under the trunk and lowering it a few inches as well. The differential case remains bolted to the crossmember.

When I lowered my differential and that end of my crossmember, I discovered that all remaining pressure was taken off the spring on that side, so that a spring-compressor wasn't required.
As I'd never replaced one of these trailing arms before, I DID acquire and insert a heavy threaded rod with washers & nuts, in place of the removed shock, to restrain the rear spring, just in case. But the differential/crossmember lowering procdure released all the remaining spring pressure, so it just cost me the extra time and a few dollars - Oh well, better safe than sorry. It's up to you if you want to take this extra precaution. Good Luck.

Happy Motoring, Mark

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DrDKW

Anyone ever broke a rear subframe bushing bolt?
http://www.peachparts.com/shopforum/diesel-discussion/73580-anyone-ever-broke-rear-subframe-bushing-bolt.html#post461406


Replacing the Rear Shocks & Springs
on the W126 1985 300SD
http://www.peachparts.com/Wikka/W126RearShocksSprings


Trailing Arm Bushing W126 1985 300SD DIY
Trailing Arm Bushing W126 1985 300SD DIY

Some comments about the other threads concerning the rear subframe/crossmember/trailing-arms.

While the manual, and some other posts talk about removing the entire rear crossmember/axle assembly, in my case it wasn't neccessary, and leaving the driveshaft and other end of the crossmember attached made the job much easier than trying to wrestle the entire crossmember/axle assembly back into place.

My '82 240D has no antilock sensors & wiring to worry about when lowering the differential and removing the trailing-arm.

I expect W123 rear springs to be a bit lighter than those in a W116/W126, and I'm sure the ones in my '82 240D have sagged a bit compared with when they were new. I can't say if installing NEW W123 springs would require a spring-compressor, but there was plenty of slack in my rear spring once the differential/subframe was lowered enough to get the trailing arm out.

None of the bolts I had to remove during my left-side trailing-arm replacement were seized or rusted.

None of my rear subframe or trailing-arm bushings appeared to be damaged, or loose enough to require new ones. The bushings may be hard, but it's a $225 car and, except for a worn steering box, it rides/handles well enough for me.

Happy Motoring, Mark

__________________
DrDKW

I've just done this job (because of wheel bearing issues) on a 123 240TD.
I didn't find I needed to drop the diff at any time, but I reckon that it's gotta be worth fitting new bushes if you've got the arm off the car cos its so simple to do...
good luck
Giles

Did you have to use a spring compressor? I found that the limiter-stop on my crossmember didn't allow the trailing-arm to drop enough to relieve the spring pressure. Lowering the differential a few inches tilted the crossmember and trailing-arm that extra bit, and allowed the spring to be lifted out by hand.

Happy Motoring, Mark

__________________
DrDKW

I did this job last fall because of a rusted trailing arm and am also doing it again on another car to renew all the bushings and get rid of surface rust before too late. I removed everything on the first car and the current car to inspect/repaint while replacing parts, so I thought I'd add my experience.

I removed the entire "axle assembly" and it took me about 3 hours from driving the car in the garage and having the entire subframe/diff/trailing arms/halfshafts assembly out in front of me. About another 1/2 hour disassembling everything for cleaning and new bushings. I made a "pumpkin" holder (like in the shop manual) out of a 2x6, two 2x4s on the sides, and a large socket bolted to the bottom. The socket fits right into the top of my hydraulic jack where the normal steel cup fits and the entire assembly is secured with a rope to the differential. I also have a spring compressor, so I pretty much followed the manual step by step. No problems reinstalling the axle using the floor jack and it seems the center of gravity is fairly on top of the jack and is quite manageable.

I liked removing the entire assembly so that I could work on it away from the car and not on my back. It looks like you've got plenty of rust on your subframe as well, so maybe a good idea to clean it, remove the surface rust, and paint it if you have the time.

Good luck with that rust!

__________________
Dave

2002 Audi S6 Avant
1983 300D
1984 300D (sold)
1990 560SEL (sold)

I presume that you removed the entire subframe?

Yes, all in one package.

__________________
Dave

2002 Audi S6 Avant
1983 300D
1984 300D (sold)
1990 560SEL (sold)

My son and I just replaced both rear trailing arms in his '82 300D with used units from Potomac German Auto. The replacements came with bushings/bearings and emergence brake cables that looked and felt good so we just used them. As posted earlier (doing one side at a time) we jacked the car up, dropped the differential a bit, removed the subframe mounting bolts, and lowered the trailing arm (bottom shock mount had rusted through so shock did not limit downward travel. I left the shock in place until the end to help contain the coil spring should it want to jump out. With the trailing arm down we could lift the spring out by hand. Front trailing arm to subframe bolt was accessbile once the subframe came down in front. Only hitch was a that one of the big subframe bolts was seized in the bushing of the subframe mount. Destroyed the mount getting the bolt out but we replaced them both anyway. Not too bad, just dirty and slow. Should last another 24 years and the car rides a bit higher with the new subframe bushings in place.