^^^^ This.

The sleeve inside the bushing is supposed to have serrated ends, so that when you tighten the front trailing-arm bolt at ride-height, the serrations bite into the side of the trailing-arm pocket and provide resistence whenever the trailing-arm moves up or down from ride-height.

If that arm was tightened at anything other than ride-height, it will cause the rubber bushing to torque against the metal sleeve constantly, and the metal sleeve can separate from the bushing, giving no resistance so your trailing-arm will drop down like that.

It is also possible that the nut for that front pivot bolt wasn't tightened enough, and those serrations acted like a saw-blade, wearing a groove in the trailing-arm pocket/shims so that metal sleeve can rotate.

None of these is optimal, but none is fatal either. After you've installed everything you're putting on the rear suspension, loosen the pivot-bolt, get those shims locked in with the big cotter-pin, get the car at ride, then tighten down the pivot-bolts to spec.

 

I've never seen one of the trailing arm bushings with serrations, got a picture? The strut rod bushings have serrated edges, but all the trailing arm bushings I've seen use a sleeve with beveled washers held on by the ends of the sleeve being flared. As far as the trailing arm not dropping like the other side, it's either the half shaft u-joint is in a bind, or the pivot bushing is in good shape and has been tightened while in the car at ride height.

 

Hopefully starting next week, I can get these things yanked out and find out what it is. Everything Ive read, Im praying the liquid wrench penetrated enough where I dont have to cut them. But reality as it may seem looks like cutting is going to be the only way to go. I bought new SS shims from willcox and have new bushings for the TAs from willcox as well. Boy and I gonna have a ton of leftover parts when I get done with the front and back. If Id of made up my mind before hand, Id of saved a ton.

 

Front A arms have serrations in the bushing sleeves to hold them when tightened at ride height.

TA bushings do not have serrations and they wouldn't work anyway because the shims are right up against the bushing washers (not the pockets) to enable setting the toe for the rear.

 

Thanks for the correction; that is right, I was thinking of the other bushings. That center sleeve does have to be expanded into a bell-shape, and has no serrations.


Still, even without the serrations, it wouldn't be designed to pivot freely on the bolt, but to be firmly held in place and the deflection ordinarily taken up by the bushing.

 

Thanks all for the info...Hope the front suspension doesnt turn into a nightmare...

 

Well, today I got around to make some progress on removing the trailing arms. After reading and hearing the horror stories of having to cut the bolts due to rust, etc, I was not looking forward to it. About a week ago I soaked the bolts and nuts in liquid wrench. Went out there today and holy smokes, used a generic hand ratchet and both came out so easy!!! When I say out, I mean the nuts are off and all I gotta do is take the bolt out. I did not continue because I had 2 questions:
1. As all can see in my pictures, when removing the half shafts, are they supposed to go in at the exact position they came out? I guess what Im asking is do I need to mark anything? Or am I just taking them out and popping new ones in? Since each side is not lined up, I wasnt sure. But it seems Ive seen or read somewhere that the exact position has to be right on target with how it was before.
2. Secondly, is there a proper technique in removing the half shafts. I have the u-joint nuts loose as well as 3 of the 4 bolts that mount to the hub. Having trouble getting to the top side bolt closest to the front of the car...

Just wanna know before going bananas...

 

If it makes it easier, it's completely okay to turn the wheels (and therefore, the half-shafts), while the car is up in the air. Especially if you raise the trailing arms to keep from binding the U-joints.

Are you replacing the U-joints, and rebuilding the half-shafts while they are out? I ended up having to cut several U-joint straps, and replacing them, the bolts, and the U-joints. I didn't mark anything. What does the shop manual say?

 

You can just pull the half shafts out, no need to mark them, there is no proper order. Like Bikespace said, you can turn them to get better access to the bolts.
I don't want to be a downer, but getting the trailing arm pivot bolt out after the nut is off is the hard part. It gets rusted into the inner bushing sleeve and will be free in either side of the frame pocket, but stuck in the inner bushing sleeve. In that case, you will need to pry out the shims on either side and get your saw in there and cut the bolt shank on either side of the arm bushing. I use a cutting torch, takes about 5 seconds, but non professionals should stay from this method due to the potential for a bad outcome.

 

Thanks guys...so where am I turning the wheels at? Obviously the wheels arent on the car so...? Hopefully the bolt isnt rusted and I can just punch it out the other side. Wishful thinking I guess. And yes, new half shafts and u-joints will be here tomorrow. They may have been fine but I decided to just go ahead and replace those as well while in there. By the time I was gonna have to pay a shop to remove the old u-joints and install the new ones, why not just go ahead and by new half shafts with new Spicer u-joints already installed.

 

Put the trans in neutral and then turn one or the rear rotors. You can insert a prybar into the outer edge of the rotor or use the prybar against the wheel studs to turn it.

 

Gotcha!

 

@'75 beat me too it, but that is exactly it. I have a specially calibrated spare scrap of wood that I use for this. You can also turn the yokes at the differential.

Good choice on the solid Spicer U-Joints. I had the time to have my half-shafts rebuilt with the trailing arms, but insisted on the Spicers, and I'm very glad I did.

Good luck with the next step! I found that a single carbide sawzall blade did a better job than a half-dozen thin bi-metal blades. Hopefully you don't need this advice, though.

 

Doing this job the first time too right now same as you so very educational! My trailing arm front bolts came out great with a drift pin and hammer. Used a bent drift pin to get the last bit out and a pry bar on the inside. Thought that was a great C3 Christmas present after reading all of the "saw all" front trailing arm bolt horror stories. Although I am wondering how much fun it is going to be to stab my new front trailing arm bolt back in from the inside, hmmmm, no much room there behind the brake bracket…...maybe you need to pull the body off to get access and maybe put a little never seize on the TA bolt for the next owner??? 2 more fun episodes coming up next for you (unless you buy rebuilt TA's), I popped the spindle out with the special press and removed the inner bearing (or outer?) next to the hub) with a large Harbor Freight bearing separator, side bolts to squeeze in under the bearing and 2 vertical bolts to push the bearing off. Spindle knocker nut installed too and tapped it while screwing in the 2 vertical bolts worked great for me to remove the bearing. And finally wondering how you tighten the front trailing arm bolt with weight on the wheel or ride height. I suppose you could install the wheels and drop the wheels down on ramps. Or better yet since I have always worked under jack stands, maybe time to finally get a lift?

Hope this might help and much thanks to you for posting this and to everyone that offered advice and help.

Happy New Year to All!

 

20mercury - I used a stiff piece of wire to thread dental floss through the front hole of the trailing arm. Then, I ran the floss through the cotter pin hole on the bolt and pulled it into position. Like you mentioned, I also coated the bolt (and alignment shims)with anti-sieze.

 

Wow great idea and Much Thanks!

Happy New Year!

 

Well as of yesterday, the half shafts came in and the old ones were removed. Just for the heck of it, even though I was able to get the nut off both sides of trailing arms, I decided to give the pin a few knocks with a hammer. Lucky me, they moved and are not seized or rusted(whew). After all the horror stories Ive heard, sounds like I got lucky! While I was under there, I thought itd be a great time to remove the rear crossmember and put new bushings in there. Took the bolt out on each side and it did not move. I do see where its connected to the differential. Does the rear diff have to be un bolted or do I just pry on the crossmember for it to fall?

 

First thing to do is put those two bolts BACK IN , or get some longer ones and use them , leave them loose so the thing doesn't fall when the two bushings let go.
To make them let go you gotta get a pry bar in between the bushing and frame and lever on it , one side then the other , back and forth , back and forth , back and forth , have a beer , back and forth , you get the idea !!!

Once its hanging on those bolts ,if your super man you can wrestle it to the ground , or get some help (better idea) I have used a trolley jack to take the weight and to roll it out from under the back

BTW don't forget to take the tail shaft off first !

Well that's one way to drop the diff , however I just re- read your post and you just want to replace those two big bushings on the cross member ? If there's no work needed on that diff , honestly I would not bother to change those bushes , for normal driving those things last forever .

 

Rather than prying, I just used a two jaw puller on each side while leaving the bolts in there loose to catch it. Those things are usually really seized on those bushings. Agree with above that normally those bushings are not needed to be replaced.

 

I agree with the previous posters. If thier is no work to do on the Differential leave it hooked up. Check the Snubber, if the bushings are crushed or begening to rot replace it. Now would be a good time to repack or replace the u-joints on the drive shaft. Good luck and be safe.

My son is doing this same repair but he had to have the Differential rebuilt with all new bearings, stub axles, posi clutches and seals. Check the end play on the stub axles. There are many threads on what to look for when doing this job.

Keep us posted you have a following. You take nice pictures post a couple.