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nate
06-20-2005, 05:43 PM
If I take my angle-o-meter (tech term here haha) and put it on the top of the ball joint with the wheels pointed straight, is that going to give me a decent measurement of caster??

I know you need a caster sweep guage to do it right, so I'm told. I never got into alignments when I worked in a shop, just grease monkey for the most part.

Anyone willing to take a few mins to check theres? Someone with a pro aligment done would help. I'm at 10* right now, I think I need to adjust. Steering is fine and all, death wobble is so-so, pinion angle is kinda shitty though.

FinlayZJ
06-20-2005, 09:25 PM
I just put this in your other thread, but it helps to visualize:

http://img.photobucket.com/albums/v296/FinlayZJ/caster.jpg

Kraqa
06-20-2005, 10:20 PM
using a angle o meter will give you a caste measurement but it wont be nearly as acurate if done right. by a computer. although i kjwo i knwo this is a total master of the obviouse post but still.



i have always done my own allignments but i never worry abotu caster i always figure out my pinion angle and leave it at that.

nate
06-20-2005, 11:09 PM
Pic isn't working at the moment. Probably work computer blocking it.

Kraga. Yeah my pinion angle isn't the best, so I think I have too much caster.

I'm not too worried about the aligment being totally accurate... -+ 1/8" is good enough for me. Figure the Jeep doesn't see alot of street use and it's going to get banged around on the trail anyway.

I think what I'm going to do is install a steering stabilizer and see what that does for me. They work on the caster.... 1 thing at a time so I can rule stuff out.

Kraqa
06-21-2005, 12:59 AM
whats you pinion angle at??

what front axle are you runngn again/


i'm runnign stock front shaft with double cardian at the t-case and abotu +5* pinion angl with no vides and almost perfict caster.

but i have a high pinion.

nate
06-21-2005, 02:27 AM
HP D30. I'll measure tonight when I get home. I have some vibes, but I think it's from the TSLs.. hard to tell for sure.

nate
06-21-2005, 04:22 AM
Yup... Where if I put the angle-o-meter on the ball joint and get 10*, I have about 10* of caster is what I was thinking.




I just put this in your other thread, but it helps to visualize:

http://img.photobucket.com/albums/v296/FinlayZJ/caster.jpg

doyll
07-28-2005, 01:03 PM
Using the ball joint method is okey IF balljoint has centered balljoint... You can get balljoing up to 2* off center .... I think ... if both top and bottom are offcenter by 2*, thats 4* more then centerlined balljoints.

Or am I all wet? :rolleyes:

nate
08-06-2005, 12:18 AM
I have normal ball joints.

LouisianaZJ
08-06-2005, 12:40 AM
there is a way to measure caster accurately using the angle on face of the diff bolts

ill see if i can find the formula or something

LouisianaZJ
08-06-2005, 12:45 AM
I check caster by using a bevel square ( adjustable square ) with a level on it against the diff cover bolt heads that are above and below the axle or use the flat round area next to this. Then use a protractor the read the degrees. I have checked many XJ's including one that was still on the showroom floor and providing you are on level ground then it should read 87.5 degrees if done as shown. This is not the true caster angle as the steering knuckles are at a different angle but they will always be relative to this angle so it is used as a reference point. But with these Dana 30 hi pinion's, you can work out the caster by the formula; 9 - diff angle = caster which Max Johnson from NAXJA feels he worked out first. This was very easy to work out as once you know what the true caster read from a print out you only have to work out what to add to the diff cover angle ( in this case -2.5 degrees ) to get to +6.5 degrees ( -2.5 + 9 = 6.5 degrees of caster ). You always start with 9 degrees and subtract the amount off vertical read on your protractor, ( -2.5 degrees ) = a caster of 6.5 degrees.

If you have a standard pinion like that come on '00-'02 XJ's then the rule does not apply as Angus from NAXJA found out. He took the measurements and compared them to a stock late model XJ and found that they run 7 degrees of caster and after having an alignment done I was able to work out that on the standard pinion ( the front uni is near the bottom of the diff ) they have a 12 degree start value instead of the 9 degrees as used above. i.e.. if you measure 5 degrees off the vertical your have 7 degrees of caster ( 12 - 5 = 7). It makes sense that the start value is higher as the pinion still has to point at the transfer case yoke ( 3 degrees below it usually ) but with a low pinion it starts off quite a bit lower to start with so needs more angle to start with.

http://www.go.jeep-xj.info/HowtoAlignment.htm

nate
08-07-2005, 03:33 PM
Now I wonder when he talked about measuring off the diff if it should be \ or /. Is / negative or positve degrees?

I adjusted mine yesterday and it was \ and I just wanted to put it closer to straight up and down, but somehow it ended up being / just a hair.

I'm gonna take it down the road and see what it does.