Yes.. Both Rear ARM spacer and Rear A-ARM ball joint can cause.

Put the Addco 1" rear sway bar and get extended swaybar links and Replace the Rear-A-ARM balljoint

 

The A-arm and the ball joint are both new. So I should install the upgraded sway bar and some extended rear links. Gotcha. I'll also make and install a 1/2 inch ball joint spacer for the A-arm. Thank you.

 

My 04 WJ has the same IRO kit, I replaced all mentioned control arms and upper rear A-arm and ball joint, new sway bar bushing’s without extended end links nor and Addco sway bar and it’s fine. So just check your sway bar bushings any wear will cause it to get a little squirrelly. Did you check your front track bar?

 

I installed the Rough Country 3" - 6" lift adjustable track bar and adjusted it three times. The first time I adjusted was off of the tires like they suggest, but I have a 0.3 degree camber on one side and a 1.2 on the other so that threw it off. ( I need to get a 1 degree offset ball joint to rectify that.) The next two measurements were off of the axle pads beside the shock mounts versus the unibody, so it is good now. I haven't replaced the rear sway bar bushings or the rear sway bar yet. Everything other than that and the axle mount front control arm bushings are new. I should replace those as well.

 

Do yourself a big favor also, get the WJ to a shop that can get it off the ground so that all 4 wheels can turn freely so that you can look for a bent axle/hub assembly.
I had a problem with a bent axle from my Daughter sliding into a ditch during a storm and I didn’t find it until I had all 4 wheels off the ground. It gave me a real weird shake at speed and would get loose while rounding a left turn at driving speeds and kept hearing a whomp, whomp, whomp that increased with speed. So while I was replacing the left rear axle shaft I also did carrier bearing/pinion and rear yolk. Good luck and keep me posted.

 

Do yourself a big favor also, get the WJ to a shop that can get it off the ground so that all 4 wheels can turn freely so that you can look for a bent axle/hub assembly.
I had a problem with a bent axle from my Daughter sliding into a ditch during a storm and I didn’t find it until I had all 4 wheels off the ground. It gave me a real weird shake at speed and would get loose while rounding a left turn at driving speeds and kept hearing a whomp, whomp, whomp that increased with speed. So while I was replacing the left rear axle shaft I also did carrier bearing/pinion and rear yolk. Good luck and keep me posted.

Oh yeah. I already did that also. LOL. This thing sat for almost 3 years. I am doing a ground-up rebuild. One front knuckle, both hubs, both shafts, new wheels and tires, all new ball joints, tie rod ends, control arms, etc. I rebuilt the trans and serviced the transfer case, put on a new valve cover gasket, new power steering pump, and lines, new rear axle shaft bearings and seals on both sides, new brakes all around including the parking shoes. N3 extended shocks, new steering damper, quick disconnect front sway bar links Man-alive... Just the front and rear sway bars and bushings as well as the axle mount front bushings are stock. Hmmm... Would it help to disconnect the rear sway bar until I can get the extended links and new bar??

 

I have the 3" IRO lift in my '03 WJ. I had the same rear sway, bump steer issues. With your 3" lift, do not use the stock sway bar links in the rear. The shorter links cause all kinds funky things to happen.

What helped with about 75% of my WJ floaty road manners, was replacing the rear upper A arms (complete with new bushings and ball joint), rear control arms and bushings and 1" Addco swaybar. BTW, i have an extra, Brand new, Addco swaybar for sale. PM me if interested.

FS: - Rear 1" Addco Sway Bar for WJ

Brand new in box 1" Heavy Duty Rear Addco sway bar fits 99-04 WJ Grand Cherokee, part # 01-684-01. Includes hardware kit # HW-684-0U. $150 Local pick up in Phoenix Arizona or Buyer pays shipping.

www.jeepgarage.org

What helped with the rest was, believe it or not, a new steering box. On a lifted vehicle a bad steering box can feel just like road/bump steer from the rear. You can adjust some of the play out of the steering box but be very careful about overdoing it, you can dangerously bind the suspension. Adjusting greatly increases wear and you will need to replace it sooner anyway.

 

Did you go with the adjustable A-arm or a stock one with a spacer for your 3"? And yes, I also thought about the steering gear. There was a ton of play prior to the front-end refresh. Everything was worn out. Afterward, it is considerably tighter, but I did think about a small adjustment to the steering gear as well. I have not done it yet, but it is another link in the chain that I am pulling on.

 

the stock WJ rear sway bar can be bent by hand. Upgrade to that rear to 1" addco and boom My Lifted 4.7 no longer had the wags.

 

YYYEEESSSS!!! Addco and RC extended end links for the win! An update on my WJ. I ordered the Addco upgraded 1" anti-sway bar and the RC 11" extended end links and after 3 weeks, they FINALLY arrived today... I spent the last hour and a half installing it all and getting it torqued in. I only had two minor issues. 1. One of the bracket mount bolts on the axle stripped out and I had to rethread the hole. 2. The bolts for the extended links were not the same thread or size as the stock mounting bolts. I had to remove the steel bolt guide from the stock bushings and use two of them in the new RC bushings so that the stock bolts could be used. Thankfully, the OD of the bolt guide was the same for both the old and new ones and only the ID was different. Now all of the "dog chasing a rabbit" road-walk at highway speeds is gone! There is still a bit of bump-steer that I must adjust out or get the adjustable front upper control arms to correct, but it is at least driveable now! Thank you all for the input and Addco suggestion!

 

Great to hear the Addco upgrade fixed the problem