Squirrely Jeep

pilot-one · 04-22-2008, 10:06 AM

In my "98 TJ I just put in a 2" ProComp lift. (springs and shocks) and had an alignment done. Everything else is stock. I also have brand new Wrangler Silent Armor tires that I put on a few weeks before the lift. It was very solid driving down the road but now it is kind of squirelly. I doesn't pull or any thing but it just isn't solid. Can this be fixed?

**Jerry Bransford** · 04-22-2008, 10:11 AM

Do you have the alignment results printout? If so, what is your caster angle and toe-in? What is your exact tire pressure as it sits now?

**ancestralworm** · 04-22-2008, 10:14 AM

if your toe is off it will make jeep meander.

pilot-one · 04-22-2008, 10:42 AM

The readout is as follows:

Left Front Right Front

Camber -0.4 Camber -1.1
Castor 4.9 Caster 5.1
Toe .13 Toe .19

I don't know what the tire pressure is since the tires are new. What should it be?

bairy · 04-22-2008, 11:23 AM

Quote:

Originally Posted by pilot-one

The readout is as follows:

Left Front Right Front

Camber -0.4 Camber -1.1
Castor 4.9 Caster 5.1
Toe .13 Toe .19

I don't know what the tire pressure is since the tires are new. What should it be?

Not sure how the machine/print out reports but if that toe is for each side
combined there is .32

That should be .063(1/16) to .125(1/8) .... right?

**Jerry Bransford** · 04-22-2008, 11:37 AM

The .13 and .19 numbers for toe-in are in degrees, not inches. .15 is correct for the toe-in per the factory spec which is given in degrees. Camber is ok, especially since it is not adjustable, and while the caster angle is a tad light, it's "ok". Ideal would be more like 5.5 to 6 degrees for a 2" lift. More caster angle would produce more a little better "return to center" of the steering wheel after a turn plus a little more stability on the highway. But 4.9 and 5.1 is not "bad", it could just be a little more. I can't figure out why they're showing two different angles for the toe-in though, that is something that could be different only for non-solid (IFS) axles. Perhaps the tires just weren't centered (via the steering wheel) when that toe-in measurement was made. Toe-in at least appears to be close to what it should be if you take the average between them.

Do you know enough about your suspension to be able to tell if your lower front control arms have cam-shaped (ecentric) washers on both sides of the forward control arm bracket so the caster angle can be adjusted? That ability was removed around the '98-99 time frame so yours may or may not have those cam bolts.

Tire pressure-wise, it's hard to say since you don't say what tire size you're running. First, make sure the left-right tire pressures are identical. If one side is different, it can cause pulling towards that side. Guessing you're probably running a 31" or 32" tire, 30-31 psi is ok. What we're concerned with is perhaps the tire shop grossly overinflated them as often happens. Tire pressure should NOT be what is molded onto the tire's sidewall, which is only the tire's maximum allowable tire pressure when it is carrying its maximum allowable weight which would of course not be the case for the Wrangler.

mudbugjr · 04-22-2008, 11:53 AM

Also measure around the circumverence of the tire. A difference of as little as an 1/8th of and inch can cause a drift or pull.

pilot-one · 04-22-2008, 12:01 PM

Do you know enough about your suspension to be able to tell if your lower front control arms have cam-shaped (ecentric) washers on both sides of the forward control arm bracket so the caster angle can be adjusted?

Yes, the cam bolts are there on the lower control arms. Should I have the shop set the caster to 6degrees? My tires are 10.5 X 31 X 15.

What about the "short" sway bar links? Is it worth putting a set of adjustable disconnects on that get the sway bar to the proper angle?

**Jerry Bransford** · 04-22-2008, 12:06 PM

Yep I'd have them rotate the cam bolts a tad to increase your caster angle a tad, 5.5 to 6 degrees is fine. Instruct them to not attempt to take the caster angle all the way back to the factory 7 degree angle which could conceivably cause a front pinion angle/u-joint vibration problem. Have them check the toe-in too. .15 is what both sides should be at.

The angle of the antiswaybar is not exactly critical and is still ok with a 2" lift. Front discos are nice to have for offroading though so if you got some, you might as well get some that can have their link length adjusted so the original slightly-above-horizontal angle can be restored.

pilot-one · 04-22-2008, 12:17 PM

Thank you Jerry!
I will get this done later today and let you know how it turns out. I will check the tire pressure too. My guess is you're right about it being too high.

pilot-one · 04-22-2008, 07:13 PM

Well I talked to the alignment guy. He is worried if we change the caster that the camber will be too far out of spec's. He said something about putting a ball joint on that can be adjust for the camber. I guess it's kind of like the 2 wheel drive Ford truck cam bolts. I don't ever recall hearing or reading of such a device on this forum specifically for the TJ.
Still go for the right caster setting?

pilot-one · 04-23-2008, 09:06 AM

Well I talked to the alignment guy. He is worried if we change the caster that the camber will be too far out of spec's. He said something about putting a ball joint on that can be adjust for the camber. I guess it's kind of like the 2 wheel drive Ford truck cam bolts. I don't ever recall hearing or reading of such a device on this forum specifically for the TJ.
Still go for the right caster setting?

**AROSETO** · 04-24-2008, 08:53 AM

Quote:

Originally Posted by pilot-one

Well I talked to the alignment guy. He is worried if we change the caster that the camber will be too far out of spec's. He said something about putting a ball joint on that can be adjust for the camber. I guess it's kind of like the 2 wheel drive Ford truck cam bolts. I don't ever recall hearing or reading of such a device on this forum specifically for the TJ.
Still go for the right caster setting?

Yes I had similar advice given by the alignment shop I went to. But my numbers were not too bad or far off. Plus I had my passenger side tierod frozen in the centerlink so they were unable to adjust my alignment. Which just gives me more of an excuse to but the Currie HD setup then get it aligned. I would like to get adjustable control arms though before I try to get it aligned again.