liondor1969

Hallo,i have a lift kit 3",i cek my pinion caster on alignment center..is 0 Is this ok ? In front,dana 44 jku 2014 ,wells 37"

tx

nthinuf

The 'Caster' is 0 degrees with a 3" lift?

How did you measure the Caster? Post the alignment printout.

liondor1969

Yes ..on the alignament.. is not ok ?

resharp001

You have 6* of caster built in to that factory axle. That means that with the pinion angle at zero, your caster is at 6*. You want the alignment spec for caster to be over 4* (factory spec is 4.2*). That means your pinion should be pointing up ~1.5* or so. nthinuf is asking for a printout of the alignment specs from the machine.

**you're posting in a thread about PR44 axles with additional caster built in, but I'm pretty sure from the other threads that you have a factory axle with the standard 6* of caster built in.

nthinuf

6* of 'Separation' built in is probably a better way to say it. (Pinion angle at 0* gives Caster of 6*. And Caster angle at 0* gives Pinion of 6*).

The way I read his first post was that he was at 0* Caster (Pinion of 6*). But reading your comment, he actually meant 0* Pinion angle, which makes a lot more sense.

liondor1969

Hallo..i buy one..
I bought a measuring device like the one in the picture,and I measured as the measurement is done in the picture ( the measurement photo is not from my car,I didn't take a picture ) but for me the measurement is 0 ..we mounted on the car the brackets from Aev. My car have 3" lift kit BDS, tires 37". normal how much should i have at the caster under the current conditions ? Thanks

resharp001

I can tell you from experience that those angle finders aren't accurate enough to read caster when placed on the pinion flange, even when accounting for garage slope. Part of the problem is they are hard to read for an application that gets down to 1/10's of a degree. Even digital angle finders are a bit hard to use because everywhere you place it on the pinion flange can get you a different ready. You really need to use the caster reading from the alignment machine.

That said, to answer your question, you want your pinion to be angled up about 1.5 degrees, give or take. I've seen angle finders off by 1-2 degrees when trying to determine pinion angle vs. what the alignment machine read for caster.

I'm not certain why you're using an angle finder when you appear to have an alignment machine that should tell you what the caster is.

Caster/pinion angle are a fixed relationship for a factory axle:
Pinion angle = 6* - caster
Caster = 6* - pinion angle

Digger 5

I didn't read every post thoroughly, did i miss something about the drive shaft angle?
No rzeppa joint shown so....
If you don't have a CV shaft, the difference between the t-case output and the pinion angle should be less than 1.5*.
If you have a CV shaft the pinion should be pointed directly at the t-case or just slightly over the t-case.
If you don't have the drive shaft set properly, a vibration- hum- can and will occur.
I've used a similar angle finder, and while not perfect, you can get the job done.

Unless I'm missing something, and I might be, the red line should always be pointed vertically. Based on your pic, your pinion is pointed down and the Jeep probably has 0* of caster. The driveshaft angle is bad and is probably causing the vibration.