Rear suspension rebuild questions

[GnatGoSplat]

Ok, just came in from poking underneath the 94 convertible and it looks like the rear suspension needs to be rebuilt.

 

 

• Both spring bushings need to be replaced, one is completely gone and the other is chewed up.
  
• 1 hub is bad, makes no noise but has noticeable play.
  
• Both bushings on one of the front transverse (or is it lateral?) links are gone. Completely gone. Link moves around with nearly 1/2" play with spring tension removed. This may be the root of all my alignment issues.
  
• Probably could use new struts.
  
• Definitely needs new jounce bumpers.
  

 

What's the easiest way to pull the links? Service manual says to drop the fuel tank, but most of us know how much fun that can be. Can it be avoided?

I had this idea:

 

1. Remove the exhaust (duals go under rear suspension instead of over, UGH).
   
2. Remove transverse spring - I have the tool, shouldn't be TOO difficult.
   
3. Thread bolts into aux springs to keep them compressed and unbolt from rear links.
   
4. Unbolt rear subframe from body, should be able to easily get to the bolts with spring out.
   
5. Leaving everything else connected, pull center subframe down, giving access to the inner link nuts and bolts.
   

 

Anyone tried it this way? Will it work? Struts should keep the wheel and knuckles attached so it's not like I'll have over a hundred pounds of suspension structure dropping.

How much does the center subframe weigh? It looks like it's made of fairly thin stamped sheetmetal, can't be more than 30lbs? Or are looks deceiving?

Think I would have problems pushing it back up and getting bolt holes re-aligned? Are the holes significantly larger than bolts where alignment to the body is critical?

Can you think of any serious flaws with this idea?

 

Also, for pulling the exhaust, any tips on that? Is disconnecting behind the cat the easiest way? Or should I remove all the hangers and just let it hang? I can see that having it out of the way would be more convenient, but not if it's a bitch to disconnect or re-align.

[Crazy K]

I would lower the exhaust onto the ground and raise the car up high, I have done this before.

 

I would lower the complete suspension onto the ground and change the bad arm, without even pulling the suspension out from under the car and change the bad arm...

 

 

I could talk you through this better than not actually, if you don;t mind a phone call...

[intern8tion9l]

i also just disconnected all the exhaust hangars and let it sit on the ground. the rear subframe is very light, like you figure. if you pull it all out you can at least get it all cleaned up and painted

[GnatGoSplat]

So it shouldn't be a problem to just disconnect the hangers and let the exhaust dangle on its own weight?

I'm thinking dropping the subframe might be less hassle than dropping the tank. Only thing is those links need an assload of torque, but I should be able to tighten them up after re-installing the rear subframe, right?

 

Ken, you still have the same # as you did when we met up?

[Schurkey]

I dropped the fuel tank of my '93 Lumina about a month ago. Not a bad job at all. The absolute worst part was re-connecting the hose from the charcoal canister to the nipple at the rear of the tank, and that was only difficult because I didn't think to do it BEFORE I had the tank completely in place, with the straps tight. Everything else is a breeze.

 

Three hoses on the front of the tank, two hoses and a wire harness at the rear. Disconnect clamps at the fuel fill tube, and fuel vent tube. Remove the heat-shield over the exhaust pipe at the front of the tank, move the exhaust. Drop two bolts at the front of the tank at the straps. Leave the rear strap bolts alone. Tank drops down and forward. Drain the tank first and it becomes very light weight.

 

If I were going to drop the rear suspension, I'd undo two bolts at the pipe-to-exhaust manifold, and the rubber hangers. Take the ENTIRE exhaust out. Simple and easy, no chance of distorting the pipe at the manifold by letting it hang from the spring-loaded bolts. Good time to inspect the pipes and heat-shields, too.

[Crazy K]

yes I do. you aren't letting the exhuast completely hang, you are resting it on the ground.

[GnatGoSplat]

Resting it on the ground, but NOT disconnecting at the manifold, right? It's a spring-loaded flex-joint if I recall correctly, so it shouldn't hurt it if I don't loosen anything and just let the rest drop, right?

 

Yeah, I've dropped tanks on 4 W-bodies over the years. I REALLY don't want to drop the tank. I hate it. The hoses are the biggest bitch and they like to fight me every time, takes all day. I did lube 'em with petroleum jelly to make them easier to re-install, but that was years ago and I'm sure they're probably stuck nice and tight by now. If dropping the rear subframe is easier, I definitely want to do it that way.

 

Torque specs on some of the suspension bolts make me nervous though. I can just picture one snapping off and becoming a nightmare. Guess I'll worry about that if it happens.

[19Cutlass94]

yeah the front of the exhaust has those springs and itll move so you can rest it right on the ground and not unbolt it by the manifold.

 

You shouldnt have to remove the tank if your just dropping the rear subframe. Its only held in by 4 bolts which have easy access. If you were just removing the front two lateral links then yes you would. But unbolt those 4 bolts and itll drop out. ( considering everything else is unbolted as well )

[intern8tion9l]

i torqued the bolts with the subframe on the ground by putting a wrench on one side and letting it tighten against the garage floor

[GnatGoSplat]

You shouldnt have to remove the tank if your just dropping the rear subframe. Its only held in by 4 bolts which have easy access. If you were just removing the front two lateral links then yes you would. But unbolt those 4 bolts and itll drop out. ( considering everything else is unbolted as well )

 

Actually, the front two lateral links are the reason I want to unbolt the subframe instead of the fuel tank. I'm imagining in my head that would be less work than dropping the tank. I was thinking I can leave everything else still bolted and just pull the center subframe down enough to get to the link nuts & bolts. With the spring out of the way (removing it to replace the spring pads anyway), I think the center should be free to drop. Then I would just remove the links one at a time and replace their bushings.

[Crazy K]

Were you going to call? saturday's are best.

 

I'll give you a walk though if you need, but you are getting the gist of the idea...

[GnatGoSplat]

It'll probably be awhile before I get to it. Can't work on it during the week since it's my wife's DD and this weekend isn't good.

 

I do have the new lateral link bushings, hub, and spring bushings already.

[Crazy K]

It'll probably be awhile before I get to it. Can't work on it during the week since it's my wife's DD and this weekend isn't good.

 

I do have the new lateral link bushings, hub, and spring bushings already.

 

unless the arm is virgin clean, I would just get completely new arms.... and it sounds too dangerous to drive. On my 94 it was behaving the same way, and it was because the arms actually had the bushing pull out of it. happened twice on the same side with both the front and rear arm. each time I swapped a used arm in as they were un-fixable. that side also needed a wheel bearing, and i believe all those parts failed due to a curb impact prior to my ownership. The original steel rims were all warped.......

[GnatGoSplat]

Hmmm, I have no idea if the bushing pulled out or not, but it feels like there is no bushing at all because I can wiggle the arm around if I unload the spring from the knuckle and it clankety-clanks. I couldn't tell by looking at it if they are un-fixable or not. I'll be quite upset if I tear it down and find it's un-fixable. Ugh. Wish I could just be rid of the car. *sigh*

[Crazy K]

<--- willing to adopt. but not yet....

 

do check on that. and give me a call and i can do a walk though for you. new arms can be had.

[Luke94vert]

<--- willing to adopt. but not yet....

 

 

Jeeze ken. You trying to get all 26,000 verts made. Lol.

 

Thou I'm not one to talk. My yard is looking like a mid 90s used gm lot. Lol.

[GnatGoSplat]

Alright, started this project. Dropped the exhaust and let it sit on the ground, I wanted to pull it off to get it out of my way, but the cat bolts appeared to be super rusted so I just decided not to mess with it. I suppose the muffler makes a good, but not particularly comfortable pillow to rest my head while I work.

Is there a tool to make pulling the exhaust out of the rubber hangers easier? Not that I need it now, just curious for future reference. I ended up just wedging 4 small flathead screwdrivers into the ends so the rubber could slide over the end, but it took some time.

 

Got the spring out, no problems there. The bushing was completely gone from one end and was easy to rip off the other because it was trashed. I roughed up the edges with my angle grinder, cleaned with lacquer thinner, and glued the new bushings on. I didn't have to use even half the adhesive that came with the kit.

 

I dropped the rear subframe without pulling the aux springs. Not sure if that was a mistake or not, but the aux springs push the subframe down, so it's too much force that I can't push it back up with my own strength. However, it seems to be no problem for me to push it up with the jack so I think I will be okay there. Worst case scenario, I have to pull the aux springs but I doubt I'll have to.

 

One thing I noticed is I don't think it's a good idea to turn the bolts around. I had originally planned to, but I noticed the design of the subframe on the front side is smooth with rounded edges and the bolt heads are recessed even though there is plenty of room. I believe recessing the bolt heads and rounding off the front is intentional so the fuel tank is not punctured in a bad rear-end accident. I think I will just reassemble it the way it was.

 

I removed the bad lateral arm. Ken is right, it's like he said, the bushings were pulled out on both ends. There was actually nothing wrong with the bushings themselves. The outer hole was badly enlarged to where there is no tension to hold the bushing in. Even the new bushings I bought, they drop in and I turn the arm around and they fall right out. The bushing stays in the inner hole, but I can easily knock it out by just tapping on it gently with a hammer. Arm needs to be replaced. Maybe I can still get my money back on the new bushings. It's probably not a good idea to replace bushings anyway since it's a press-fit design and there's a good chance new ones won't fit as tight as original and would pull out.

 

I went ahead and replaced the bad hub while I had it apart. Rotor was stuck solid, I tried penetrating oil, and a crazy amount of hammering, but that didn't unstuck it. I then tried using a torch on it, and then it came off on the second whack. It was smooth sailing after that. The hub was definitely bad (significant play), but it made no noise.

 

Time to order a new arm.

Edited November 3, 2012 by GnatGoSplat

[Crazy K]

do take pics of the failed part. I have seen it happen but have no documented pics.

 

 

Which arm failed? front or rear?

 

does this car have a REAR swaybar? (i think it should being a 94 3.4 vert)

 

I suggest you go ahead and order the Dorman trailing arms and the adjustable arms used on gen 2 cars for the rear, which makes adjusting the toe easier. discard the aux springs and be done with them.

DORMAN Part # 905501 boxed trailing arm

DORMAN Part # 905502 adjustable second gen lateral link/ track arms/ spindle rods

 

seems I am still looking for the new front "track arms" that fit our cars. about to suggest that you get the gen 2 fronts and have them cut and modified to fit the front............

Edited November 4, 2012 by Crazy K

[GnatGoSplat]

I didn't take pics, but I did take a vid. I didn't think pics would be very good to illustrate the looseness of the bushing.

 

It was the front arm.

 

Yes, it does have a rear sway bar.

 

Ken, those are good suggestions, but I think I will just replace the bad lateral arm with an OEM replacement and be done with it. I have no interest whatsoever in upgrades to this car or spending money to replace parts that aren't defective. I also don't know a guy who could weld up the front ones for me and have no interest or time to find someone. Also one drawback to losing the aux springs is the ride height increases about 1/2", so I'll keep them since I don't plan to replace the rear spring with a lowering spring.

[Garrett Powered]

I know like 3-4 guys off hand and its an easy procedure, that's why I decided I am doing my tube lats. also want a z-34 sway bar for the back before I start. I already got the exhaust and front sway bar off a similar car installed on to my car by the previous owner..

[White93z34]

If you need to use the Kent-moore aux spring compressor i can loan it to you.

[GnatGoSplat]

Yeah, I'd definitely do the tube lats if I wanted to keep the car forever, but I've been wanting to sell it since the last presidential elections.

I did find a NOS OEM lateral link on eBay for $41 shipped and bought it, assuming my parts catalog is correct and the auction description is correct (he had the wrong p/n in the title, but right p/n in the description and photo).

 

While tugging and pulling on suspension parts and checking that struts still had some dampening ability, I discovered the right side upper strut mount was bad. I happen to have a perfect spare I saved years ago because it looked brand new, but I can't get it on because while trying to get the nut off the top, my TORX stripped out. FFFFFFFUUUUUU!!! Looks like I'll need to pull the strut and hit it with the impact to get that damn nut off. I'll need to compress the aux spring to get the strut off, but the angles of the suspension parts are preventing me from compressing it with a bolt. I'll probably have to get everything back together before it can be compressed with a bolt.

 

@Chris, thanks for the offer. I may take you up on it if I can't get it to where I can compress it with a bolt.

[GnatGoSplat]

Alright, got a new link during the week and got it all back together today, but it pulls pretty badly to the right. Gotta turn the wheel to the left maybe 30-35 degrees. It tracked straight before. I wouldn't think just changing a link would make that much difference.

I'm starting to wonder if dropping the rear subframe was a mistake. It has guide pins, but only on the right side is the guide pin hole round, the other is oval by design making me think the rear subframe needs to be aligned too. I did initially bolt it loosely to see if it moves around, but it didn't move around much, so I don't know.

Guess maybe I should have dropped the tank so I wouldn't have to worry about subframe realignment.

 

Think Sears would be able to get it aligned properly? The car has never been previously aligned since it doesn't have a rear toe kit installed.

 

Oh, and the exhaust is noisier than ever. Ugh.

[Crazy K]

learn:

 

 

the rear toe is adjusted with the inner upper bolt on the rear lateral links, they are mounted in a slotted hole. Hence why I suggest new arms from a gen 2 which can be adjusted much easier.

 

for now, at least get a reading to see estimate your toe... I would guess from your description that the left rear tire is toe in way too far, which means it point in.

 

ALTERNATIVELY.... maybe it is closer to straighter then before, and the front was adjusted for an out of adjustment rear.... as a minimum, go get a free alignment check and post results.

Edited November 11, 2012 by Crazy K

[Schurkey]

I'm starting to wonder if dropping the rear subframe was a mistake. It has guide pins, but only on the right side is the guide pin hole round, the other is oval by design making me think the rear subframe needs to be aligned too. I did initially bolt it loosely to see if it moves around, but it didn't move around much, so I don't know.

Guess maybe I should have dropped the tank so I wouldn't have to worry about subframe realignment.

 

Think Sears would be able to get it aligned properly?

Sears would not be my first choice.

 

You know that the car tracked straight, prior to you dropping the rear suspension.

 

You know which way the car tracks now.

 

Loosen the rear subframe, pivot it back where it was, tighten the bolts. See what happens.