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-   -   Rear subframe removal and bushing replacement (http://www.peachparts.com/shopforum/diesel-discussion/276507-rear-subframe-removal-bushing-replacement.html)

dieseldan44 08-14-2010 01:17 PM

Quote:

Originally Posted by Whiskeydan (Post 2525210)
When tightening the bushing bolts you need to make sure the trailing arms are in the correct position. The differential and axles need to be straight so, I had to temporarily install the axles and old differential to make sure the bushings do not get twisted when the car is back on the ground.

Axle stubs on both ends MUST be in the same plane and aligned with the differential. Trailing arms in the same resting position as it would be with the weight of the car off the jacks.

Failure to do this will result in early trailing arm bushung failure. :eek:

Whiskeydan and all,

I was thinking to just leave those bolts slightly loose, bolt up the subframe/trailing arms, install the axles, and then use floor jacks to achieve the straightened position as outlined in FSM article 35-110.

I would install the springs afterward with the spring compressor.

Does this make sense?

dieseldan44 08-14-2010 01:25 PM

Rear Wheel Bearings
 
My two rear wheel bearings have different amounts of force needed to turn them. They both roll fine, but the difference it takes to turn them by hand is noticeable.

I have seen dmorrisons DIY write up on rear bearings and I don't know if I have the time and tools needed to deal with that right now (I'm in pretty deep right now, dont you think ? :D )

Could I take my uninstalled trailing arms to an indy and have them re-pack the bearings and put new races in?

Or should I not worry about it until it presents a problem?

Stretch 08-14-2010 01:55 PM

Quote:

Originally Posted by dieseldan44 (Post 2525236)
My two rear wheel bearings have different amounts of force needed to turn them. They both roll fine, but the difference it takes to turn them by hand is noticeable.

I have seen dmorrisons DIY write up on rear bearings and I don't know if I have the time and tools needed to deal with that right now (I'm in pretty deep right now, dont you think ? :D )

Could I take my uninstalled trailing arms to an indy and have them re-pack the bearings and put new races in?

Or should I not worry about it until it presents a problem?


If you do that it won't be a weekend job anymore...

Take a look at what I did:-

http://www.peachparts.com/shopforum/diesel-discussion/277341-w123-rear-wheel-bearing-removal-help-needed.html

In the end I took them apart and re-greased as the bearings were fine. However, it is a fiddly job and you need dealer supplied spares (if you're not prepared to buy a whole bearing kit just for the seals / crush washers / rings)

Whiskeydan 08-14-2010 01:56 PM

Quote:

Originally Posted by dieseldan44 (Post 2525231)
Whiskeydan and all,

I was thinking to just leave those bolts slightly loose, bolt up the subframe/trailing arms, install the axles, and then use floor jacks to achieve the straightened position as outlined in FSM article 35-110.

I would install the springs afterward with the spring compressor.

Does this make sense?

It would be easy to do with a string thru the hubs. Raise the subframe ass'y and measure the distance from the string to where the diff mounts to the sub frame. It should be the same as the differential 'top to axle hole'. then tighten the bushing bolts. This should get it close enough.
I don't think you can tighten the bolts when the ass'y is installed.

You just don't want to tighten them with the trailing arms in the fully up or down position. The need to be close to resting (car on the ground) position.

Whiskeydan 08-14-2010 01:58 PM

Quote:

Originally Posted by dieseldan44 (Post 2525236)
My two rear wheel bearings have different amounts of force needed to turn them. They both roll fine, but the difference it takes to turn them by hand is noticeable.

I have seen dmorrisons DIY write up on rear bearings and I don't know if I have the time and tools needed to deal with that right now (I'm in pretty deep right now, dont you think ? :D )

Could I take my uninstalled trailing arms to an indy and have them re-pack the bearings and put new races in?

Or should I not worry about it until it presents a problem?

If they are running smooth and not loose I wouldn't worry about it.

Stretch 08-14-2010 02:00 PM

Quote:

Originally Posted by dieseldan44 (Post 2525231)
Whiskeydan and all,

I was thinking to just leave those bolts slightly loose, bolt up the subframe/trailing arms, install the axles, and then use floor jacks to achieve the straightened position as outlined in FSM article 35-110.

I would install the springs afterward with the spring compressor.

Does this make sense?

The point about this is that you don't bugger up your trailing arm bushings... I worked out you could get it all level by putting the diff on a bit of wood (sorry I know... wood again) to get the correct horizontal height. I admit I didn't attach the axles until later - I'm hoping that won't make too much difference - we'll see!

I put the springs in last after I got everything aligned.

dieseldan44 08-15-2010 02:02 PM

Im at the degreasing and washing stage now prepping for paint...

Regarding the diff - I covered the holes as best I could and plugged the axle holes with paper towels. I don't think any water got in it. Regardless, would it be a bad idea to clean it out with brake cleaner before re-assembly to make sure everything is dry?


Things are looking great....

Stretch 08-15-2010 03:30 PM

Great stuff
 
1 Attachment(s)
Quote:

Originally Posted by dieseldan44 (Post 2525810)
Im at the degreasing and washing stage now prepping for paint...

Regarding the diff - I covered the holes as best I could and plugged the axle holes with paper towels. I don't think any water got in it. Regardless, would it be a bad idea to clean it out with brake cleaner before re-assembly to make sure everything is dry?


Things are looking great....

Well done - keep on going.

Here's a picture of the inside of my diff after I cleaned it out

dieseldan44 08-15-2010 05:50 PM

So brake cleaner in the diff is OK?


Now im debating whether to replace the side seals...they dont leak.

Whiskeydan 08-15-2010 10:35 PM

Quote:

Originally Posted by dieseldan44 (Post 2525966)
So brake cleaner in the diff is OK?


Now im debating whether to replace the side seals...they dont leak.

I cleaned mine out with degreaser and a pressure washer. Blew it out to dry with compressed air, flushed with a thin oil and left it in the sun.

Couldn't be any worse than the nasties that I found in there when I pulled the cover.

dieseldan44 08-15-2010 11:59 PM

Quote:

Originally Posted by Whiskeydan (Post 2526119)
I cleaned mine out with degreaser and a pressure washer. Blew it out to dry with compressed air, flushed with a thin oil and left it in the sun.

Couldn't be any worse than the nasties that I found in there when I pulled the cover.

Sounds like a plan to me. I think I'll put new seals in too. Ill hopefully never have the diff out like this again.


All the big parts are now de-resuted, stripped and sanded, degreased, acid etched and ready for POR-15. Rain moving in prevented any additional progress.

Tomorrow I rebuild the axles, and prep the bottom of the car for paint. I also have a spun bolt mount to attend to, and I'll pull the rest of the driveshaft in preparation for the re-install. It'll be raining, no POR-15 work :-(

Thanks agin Army, charmalu and Whiskeydan...

Phillytwotank 05-04-2012 08:58 PM

FYI
 
For anyone who is looking to replace the rear subframe mounts in their w123... An easy way to seat the new mounts to the subframe is to use a 6" C clamp. I didn't see it mentioned anywhere in any of the DIY write ups. FSM calls for a special tool for the job but the c clamp worked great.

minimike1 06-17-2012 12:48 AM

I've got to replace the rear subframe mounts (front donuts) and also the rear trailing arm bushings (all 4 bushings). Do I have to take out the rear axle/diff to do this job? I'm hoping to just lower each side. Car is on a 2 post lift and I've got a transmission jack, screw post style. Any help would be appreciated. Also, any tips on removal and replacement on the trailing arms? I would not think a car should be designed to remove such a large assembly to replace these parts.

Stretch 06-17-2012 01:11 PM

Quote:

Originally Posted by minimike1 (Post 2956961)
I've got to replace the rear subframe mounts (front donuts) and also the rear trailing arm bushings (all 4 bushings). Do I have to take out the rear axle/diff to do this job? I'm hoping to just lower each side. Car is on a 2 post lift and I've got a transmission jack, screw post style. Any help would be appreciated. Also, any tips on removal and replacement on the trailing arms? I would not think a car should be designed to remove such a large assembly to replace these parts.

Since starting this thread I've taken the whole car to bits - so everything has been / was removed.

I think you are going to find it easier to remove the whole sub frame with the differential still attached to the sub frame especially if you are doing the trailing arm bushings.

Haynes says that if you are just doing the sub frame bushings you can do one side at a time by dropping them down on a jack. My problem with this recommendation is that this will (in my opinion) twist the mount to the rear of the differential excessively. OK if you are replacing it anyway (and do it as the last thing) but the sub frame mounts get twisted quite a bit doing it this way too. Using this method you'll be twisting one new sub frame mount quite a bit to get the last mount in place.

I've read that some people have done trailing arm bushings without removing them all the way from the car - I say make your life easier! You'd have to lower the sub frame quite a way to be able to remove the nuts on the bolts that hold the sub frame in place anyway... Removing 25+ year old bushings on a trailing arm under a car? No thanks - much easier on a bench!

Best tip I've picked up since starting this thread is to leave the wheels on the hubs and roll the whole sub frame with everything still on it out from under the car. It works a treat so long as you can raise the car up high enough at the back.

Stretch 06-17-2012 01:28 PM

Here's a picture showing what I mean about the sub frame just being wheeled out

http://www.peachparts.com/shopforum/...oved-again.jpg

Does anyone want step by step instructions for this?


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