mphilleo

I don't mean to spam you guys with a bunch of threads, but I'm just trying to hammer out the issues on my JKU as I go. You've all been of help to me and I appreciate it. This one has been a head scratcher for me, but maybe you guys have an idea.

Recently, I noticed a popping sound while making a low speed U-turn (not quite at full lock). It's a single pop, brief and not terribly loud. This will also usually occur when I'm going about 15mph turning left in a roundabout I take to work. So I decided to check the installation and torque of my rear end components. I was able to put a little more torque on the trackbar relocation mount bolt and the driver side rear control arms, but maybe a few lb ft. Everything else seemed to be to spec, swaybar end links, swaybar, track bar, control arms, anything I could think of checking. I didn't torque the body mounts again but they did seem fine. The coil springs looked to be seated, but just as an experiment, I used hose clamps to retain the bottom of the springs to the seat on the axle in case they were shifting. No change.

Not sure if it's a red herring, but I noticed a dot of foreign substance on the inside sidewall of my rear driver side tire. It was some of the D-bushing grease supplied with the swaybar kit I installed. This suggests to me that the swaybar may be flexing or the end links are allowing excess flex or lateral movement, which would result in the contact of my tire on the swaybar/bushing, leaving the grease on it. But there's also always the chance that I accidentally got a dab of it on the tire while installing.

I'm at wits end on this. My next steps are to lubricate the parking brake cable (works fine though) and the folding rear seat hinges, just in case. I don't really want to, but it looks like I might have to pull my rear control arms to check for wallowing in the holes. Beyond that, I'm stumped. Thanks, guys.

resharp001

This sound commonly points to an undertorqued sway bar link bolt. An easy way to replicate suspension related sounds in the rear is to get on one side of the tub and with both hands push it to the other side. You can get the body rocking back and forth really easily which will replicate most sounds and help you pinpoint it. It'd put me $5 on the sway bar link bolt.

mphilleo

Thanks for that, I'll take a closer look at it. Since the sway bar links on this Jeep are old-as-the-hills Rough Country units, I already bought some beefier end links from Hellwig, since that's where I got my rear sway bar from (really happy with it). I'll install those this weekend and make sure everything is torqued properly.

resharp001

Usually you wouldn't want a super beefy sway bar in back, just FYI. That factory rear sway bar isn't all that beefy which is what allows the rear axle to articulate some without disconnecting the links like you have to do up front, yet it's still enough that it helps keep some road manners. I'd presume the Helwig replacement is a much more stout bar and might hinder that if you offroad much more than fireroads or back country roads.

mphilleo

Good point. I'd thought about that, although to be honest, I'm one of those guys who mostly uses his Jeep for tooling around with the wife and kids and commuting. I'd probably say that the most this rig will see is some dirt or gravel roads unless I get a wild hair. I might have mentioned it in another post, but it does have a 3.25" RC lift from the previous owner. Would that minimize any of the articulation issues you mentioned with the rear sway bar? The main reason I got it was because it helps stabilize the truck while commuting here in North Dakota (I pretty much have 8-18 MPH winds, up to 28 on average). I'm honestly not sure what did more for that, the Hellwig rear sway bar or the Rancho RS9000 shocks I installed. But together it did make it feel less "tippy" when getting pushed around the road.

resharp001

If that's how you're using the jeep it's not a big deal then. What do you have going on with the rear track bar? With the lift, keeping that mounted as high and at as flat an angle as possible will help with the roll center in the rear. Usually this is done by adding a raised TB bracket on the axle-side. Some lifts like RC will use a lowered bracket on the frame side which is not as ideal. Wonder if that was coming into play a bit on your jeep as well.

mphilleo

It looks like the kit came with a trackbar relocation bracket or one was added later. Here's a few pictures. They're not great, but it gives you a general idea of what's going on back there.

resharp001

Looks like you're in good shape there.

mphilleo

Thanks, it's nice to get a second set of eyes on my setup. Would you say I might as well try popping on those new Hellwig end links, center and torque everything propely and see how it goes? If nothing else, the bushings will be fresh on them.

Sixty4x4

Hard to tell but that sway bar link bolt could be loose on bottom right but could be picture even though you say it is all checked. Happened to me on front - could have sworn it was torqued up but 6 months later she was loose. Tightened and no more noises.
If you can afford it get some longer (MC brand suggestion) brake lines and remove the hard line drop brackets and get the hard line up behind the chassis for protection. I had a stick come up, hook the hard line below the chassis and twist it around. Straightened it and it snapped. Now have a new hard line across from right side to near Evap Canister - cost $90. You know those forestry roads with that 6ft long branch that will jump up and bend a brake line right??