Clunk after installing new sway bars

After I installed my original sway bars, I had a clunk too. The instructions had a note about which hole in the bar not to use, and of course, I got them mixed up. So the bolts would get into the springs when the sway bar shifted in its supports during driving.

Leon

Check the RR lower spring perch for a shiny spot or dent where the bar is hitting it under full compression. To fix it, you may have to use a different endlink hole. The middle hole should be OK. If you don't like the resulting handling balance, correct it by adjusting the front-rear camber bias at your next alignment.

On my '94 with FM sways, I use the middle hole in the 5/8" rear bar, the outer hole in the 7/8" front bar, and a 0.55° camber bias. The result is the tiniest bit on the understeer side of dead neutral. Just enough understeer that I don't have to make constant corrections to stay in the center of a highway lane.

I used the FM suggested setting for my car. I didn't see any marks on my springs, but to be sure, I painted my springs near the sway bar with white house paint. I'll test it tomorrow after the paint drys.

My rear bar is using the middle hole and the front is using the outside hole. I don't see any marks on the perch or springs. I went ahead and painted the lower inside of my springs and perch white, so I can test again tomorrow. I also balanced my car on 3 wheels, front on jacks, rear right tire on an 8" block, and the rear left tire about 1" off the ground. I checked the sway bars with this heavy static loading of the rear sway bars and there was still decent space between the spring plane and sway bar.

If I don't see any marks on the paint tomorrow, I'll try different sway bar mount holes. I did notice my end link bushing are worn. Any change this can cause the clunking noise? My car only has 40K.

Thanks.

After farther investigation, I found that my rear sway bars are moving left and right about 1" to 1.5". The bars are not hitting the springs or perch. I'm guessing the clunking noise is from the bars hitting the piece of frame its mounted on.

I'm under the impression that the bars should not move left and right. Any ideas how I can fix this?

Thanks, Mack

Did you use the lube that (usually) comes with the new bars? Maybe it's grabbing and letting loose instead of sliding thru the bushings as intended.

Good Luck, Chris

99BBB

I got one small tube from FM and I used it all on the front bar. I used Pennzoil Wheel Bearing Grease instead for the rear

. Do you recommend a different grease? I only install the bars2 weeks ago and the clunking noise was there almost right away.

Thanks, Mack

Waterproof wheel bearing grease for boat trailers, from a boat store.

To prevent lateral shifting, you can wrap a piece of old radiator hose around the bar outboard of each frame bushing, secured with a hose clamp.

FWIW, my bars never move sideways. Dunno why some do and some don't.

I bought my sticky green marine wheel bearing grease from Autozone about

7 years ago. I would think that any major auto parts store would carry it, "probably" at a somewhat lower price, not that a tube of grease is that expensive to begin with.

After using it on 4 different sway bar installations, it still at least

90% full.

Pat

As Lanny recommended, waterproof wheel bearing grease.

Still, since you used any type of bearing grease during the rear install, it probably is not catching and letting go like Chris suggested as a possibility.

The grease that you used will wash out from driving in the rain much faster than grease designed for trailers that regularly get pushed into the water, but the result will most likely be an irritating squeak.

I think that I have only re-applied the grease to one set of sway bar bushings, and that was on my daily driver which saw a lot of rain driving, and it still took 4 years or more before it needed attention.

Pat

My bar has only been on for 2 weeks, so I don't think the grease is the issue. It still moves freely in the bracket. I'll get so get some marina quality grease before the rain season starts.

The guy at FM also suggested the using a hose like you suggested. That seem to dampen the noise the first couple of times, but after that, it same sound returned. There was too much lateral force for the clamp and hose to stay in place.

For a temporary fix, I'm going to use the same hose and clamp as a buffer between the two piece of banging metal. I'll still investigating a permanent solution.

You gotta clean the grease off the bar first.

Did you lower the car before doing the final bolt tightening?

Leon

I wiped the grease off with a rag, but maybe that's not enough. Let me try some cleaners and really get a good cleaning.

Yes. I got the bolts on while it was still jacked up, but I tighten and torque the bar on the ground. When you attached your end links to the bar, did it fit easily, or did you have to muscle it in a bit?

With my FM bars, the endlinks fit fine...provided I went with the bar holes they were telling me to use: outer front, middle rear. Anything else would've been a real struggle.

Those endlinks knew what they were doing; the handling balance was close to perfect with my stock springs. The fine tuning was a matter of adjusting the front-rear camber bias on the alignment rack.

The noise is gone. I went to the hardware store and got a few screw type tube clamps instead of the spring type I was using. I also got a foot of 5/8" washer hose which is a perfect fit for the rear FM bar. I also used WD-40 and a rough sponge pad to clean the grease off the bar. As an added precaution, I put some hose over the part of the bar that used to bump the frame(I was under the car anyways and had some extra hose). I did some test and the sway bar is not moving. Hopefully, it'll hold up at Thunderhill on Saturday.

I really appreciate everyone's help.

Have fun. I hope it is still like when I was there way back. Some of the best track days I have gone to.

Leon

The rubber hose clamps did not hold up during track day. At the end of the day, I notice that they moved about 1 inch. Since I placed some of the rubber hose at the two bends that bumped the frame, I noticed much less noise when it did bump. The rubber hose clamps did hold up well to a week of street driving with no movement.

I'll be trying some adjustable end links soon to see if they help. Plus I want to be able to adjust the sway bars settings.