should i take out the front adjustable track bar and put in the origanal? Or leave that and take out the rear relocation track bar bracket?

 

do i need to buy any additional parts to fix this?

 

i dont know much about thrust angle, but im going to agree with an earlier post, that something is bent somewhere. for a measurement that should be zero, u would have to damage something to affect it. u shoouldnt have to remove any parts unless they are damaged. but u may have to remove parts and test again to do trial and error and if it measures ok, then put those parts back on

 

17 min is just over a quarter of 1 degree. Assuming a radius of 37" (half the width of the JK which ~74" wide), one wheel is 0.18" further forward and the other 0.18" further back (rotated in the horizontal plane around the middle point; say the pinion).

Tan (0.28 deg) = 0.00489 * 37" = 0.18"

It's late for me, so my math may be off, but if not that is a pretty small thrust angle and IMO probably negligible. Although 0.36" total is starting to be not that small. A good alignment mechanic can advise better.

I don't know how you measure the angle so accurately, but part of it could the measurement error.

I still think a bracket is probably bent.

The case I saw in the past was slightly obvious to the naked eye by looking at the rear tires in each fender well.

 

Thank you very much. I am going to check if somthing looks bent

 

My calculation was bugging me because the trig didn't sound right.
I knew there had to be a reason I flunked out of high school.

I should have used the Sine (angle) not the tangent, but for very small angles they are almost the same. So my comments on the previous post still hold true.

I can post a diagram tomorrow.

 

Thank you.

 

Okay, this has been bouncing around in my brain. If your trackbar is not set at center and you are running stock control arms, then wouldn't it cause the thrust angle be off a little? Have you checked your trackbar measurement? There's a writeup on it somewhere. The cliff notes are take a straight board that will sit higher than your tire when on its end. Set the board on edge so one edge divides the tire in half. Measure from the top of the tire into the inner well of the fender -find some common visual point so you can measure both sides. Then compare. If you're off by more than a cenitmeter, I'd say re-set your trackbar then have that angle checked again. I wouldn't go yanking or replacing parts until I'd made sure everything's set correctly to begin with.

 

i had a look at my axles today. The rear one is perfect. On the front the left front wheel sticks out more. (right hand drive) i am going to adjust my front track bar so it is in the middle. Will this fix the Thrust angle? It makes sense that it would or am i wrong?

 

ok i took out the front adjustable track bar and that made all the diffrence. Also had front lower control arms fitted. Wow what an improvement.

Thanks to all for the help