adriaanvn99

Have had a strange occurrence after doing some stuff to the Jeep. I was running a RC 3" lift with full leaf packs originally, and the XJ was very tolerable on the road.

Recently, I had my whole front end rebuilt and a lunchbox locker installed. I had a shop install the locker, as well as all new bearings, inner seals, pinion seal, upper and lower balljoints and new axle shaft U joints. I also swapped out my RC lift with a RE 3.5" coil springs and full leaf pack, with CavFab adjustable upper control arms and an IRO steering rod. I also replaced my trans mount with a poly daystar one. Rotors, calipers and brake pads are all new too, with a full brake fluid flush.

I got the alignment done at a shop to ensure that everything was within spec. Here is where things get odd. Whilst driving around 40 mph, the Jeep tracks as straight as an arrow and is very tolerable. When I am driving on the highway around 60-65 mph, I start to get a little vibration and the Jeep starts to pull side to side, and I have to fight the steering a little bit to keep it straight. I haven't had any real issues turning or taking a curve with speed. When I take my foot of the pedal, there is a slight grind almost for half a second. It is not there when driving normally or accelerating. When applying brakes the Jeep also stops dead straight and doesn't pull to any particular side.

My main concern is that the shop that did the front end did not setup the backlash correctly (there was no marking compound on the ring gear when I got it back). I understand that it is just a measurement, but with all new components (Spicer U joints, Timken wheel hub bearings, XRF balljoints) I am struggling to believe that it could be something that is already failing. Could incorrect backlash be the cause for the side to side pulling?

If not, then I will need to address the tires for uneven wear, a bad driveshaft U joint (for the vibes), incorrect pinion angle or the RC shocks which have gone bad.

Any help/advice appreciated!

nardey11

subbed because mine is doing the same thing.

Bugout4x4

Are the front and rear tires all the same make, model and size?

Tsaani97xj

Sounds like tram lining to me. What is your tire pressure at? You can take out some air and see if it improves.

adriaanvn99

Yes they are. All 305/70R16 on Pro Comp alloys. I do have a slight uneven tread wear on the front right. Will swop front and back to determine exactly. I am due for new tires soon anyways.

adriaanvn99

I was running at 1.8 bar so I aired up to 2.3 bar and it was slightly better, but not exactly. I am guessing it might be my draglink at the passenger side knuckle, as that was the only TRE not replaced. Although when inspected, it didn't have too much play and was holding grease.

Bugout4x4

That is the way to check. You are right on it and know whats up.