Horrible rear end clunking/clanking

[Vapour Trails]

In past few months I've developed a clunk from the rear suspension. It started out pretty mild and not all that consistent. I thought it could be the DS, which is pretty noisey most of the time. I installed polyball J&M LCAs in July and didn't have any noise/clunking immediately after installation. Bolts were torqued to spec with blue loctite. I checked the torque on the upper shock nuts a few weeks ago and they seemed fine. Yesterday I firmed up the rear shocks (D-specs) and added a few psi to the rear tires. All of a sudden I got wicked loud clanking from the rear end over rough terrain. I've thought about the mufflers possibly striking the underside of the car, but they never did this before and the hangers/mounts should be tight. It definately sounds like metal-metal contact. I'm going to get under the car today and check the tightness of all fasteners but I'm starting to wonder if I've torn the diff to UCA bushing completely. The UCA is currently stock. Anybody else destroy this bushing with a stock UCA? The rear suspension is: Steeda sport springs, d-specs, J&M LCAs, the rest is stock.

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[RodeoFlyer]

Most Likely -

Bushing blown out on one of the LCA's. It happens with virtually all of the poly/poly bushing'd LCA's. Before you mention the poly ball thing (I had a pair before they went to market)- I blew out the driver/axle side bushing. It looks good on paper, but doesn't work all that well.

If that's not it, check -

UCA mounting bolt (arm-mount)

UCA bushing (the one on the diff)

[F1Fan]

Originally Posted by Vapour Trails

In past few months I've developed a clunk from the rear suspension. It started out pretty mild and not all that consistent. I thought it could be the DS, which is pretty noisey most of the time.

I installed polyball J&M LCAs in July and didn't have any noise/clunking immediately after installation. Bolts were torqued to spec with blue loctite.

I checked the torque on the upper shock nuts a few weeks ago and they seemed fine.

Yesterday I firmed up the rear shocks (D-specs) and added a few psi to the rear tires. All of a sudden I got wicked loud clanking from the rear end over rough terrain. I've thought about the mufflers possibly striking the underside of the car, but they never did this before and the hangers/mounts should be tight. It definately sounds like metal-metal contact.

I'm going to get under the car today and check the tightness of all fasteners but I'm starting to wonder if I've torn the diff to UCA bushing completely. The UCA is currently stock. Anybody else destroy this bushing with a stock UCA?

The rear suspension is: Steeda sport springs, d-specs, J&M LCAs, the rest is stock.

Hi Vapor,

How many miles have you put on the car since you installed the Steeda Adjustable Panhard Bar? If you are over 15K on the Panhard bar pull it out and check the bushings. If you drive your car hard these get compressed and distorted failing to return to shape and do not locate the axle well. If you keep going it turns into a clunk and can feel weird when cornering hard.

If it is not the Panhard bar check the LCA's like Rodeo suggested. I had an on going problem with my Steeda adjustable LCA bushing sleeves collapsing and bending. I think the wear was made worse by my constant disassembly and reassembly of my suspension bits. Steeda sent me some replacement bushings and sleeves but I figured they would fail the same way so I modified them. I had some O.E. dimension bushing sleeves machined from mild steel stock installed in some fresh Steeda bushings that were drilled out to fit my custom machined bushing sleeves. No problems with the chassis side LCA's anymore. I'm running Teflon lined rod-ends on the axle end because I think you can improve the wear and tear on the chassis side LCA bushings by installing lined rod-ends or Johnnie Joints to allow the LCA's to articulate more freely and reduce the preload on the bushings.

HTH!

[Rubrignitz]

What happened to F1FAN? I'm now running into many of the issues he explained on this board. Bushing issues etc. I've defeated most of the front suspension issues on this car but the solid rear is definitely a science and give/take between compliance, traction, handling. Rear clunks seem to be inevitable unless you have an adjustable upper CA that articulates very, very well ala metco. Someone has to make a quiet rear CA setup with poly bushings.

[RodeoFlyer]

Originally Posted by Rubrignitz

What happened to F1FAN? I'm now running into many of the issues he explained on this board. Bushing issues etc. I've defeated most of the front suspension issues on this car but the solid rear is definitely a science and give/take between compliance, traction, handling. Rear clunks seem to be inevitable unless you have an adjustable upper CA that articulates very, very well ala metco. Someone has to make a quiet rear CA setup with poly bushings.

F1Fan grew tired of the asshattery on this forum, and spends his time on others. i can track him down.

I had the Metco before it went on the market. It's bulk makes it a problem on a lowered car. It's well made - just not good for what we do.

Somebody does make a quiet upper arm - FORD. I run the stock one and do just fine. Drive around it.

[6-Speed]

Originally Posted by Vapour Trails

In past few months I've developed a clunk from the rear suspension.

The rear suspension is: Steeda sport springs, d-specs, J&M LCAs, the rest is stock.

Did you ever figure out the source of the clunk?