Pinion angle question

[myjeep]

ive red alot of threads on many forums and cant get a straight answer.

need to find out the pinion angle for the front and rear axles and font caster angle.

[4.3LXJ]

Here you go straight out of our how to section.

http://www.xjtalk.com/showthread.php?t=7299

Instead of an angle finder you can now use a smart phone with a free leveler app. To get the castor angle lay your angle finder or smart phone on the top of the ball joint. Not sure if the ball joint is flat on top for the Jimmy, but there should be a flat surface there somewhere, unless of course that is a Jeep axle in the front.

[myjeep]

lp dana 30 front

8.25 rear

kit
https://www.4wdfactory.com/store/products/-S10-Coil-Spring-Solid-Axle-Conversion-Builder's-Kit-.html

the only thing is for my front the cardian joint is at the front pinion yoke cuz i have the 231c transfer case, and the driveshaft company couldnt find a yoke to put the cardian joint at the transfer case but he found one for the dana 30. told me it wouldnt matter which end the cardian joint is.........

i only have vibes at 5 mph and want to make shure the angles are correct before i look at other stuff.

[4.3LXJ]

Well, it does make a difference which end the cardan joint is on. Look at the diagram that has the double cardan joint, if that is what you have. The pinion needs to be a straight shot off the drive shaft, no more than 4° angle. Can you give me some pics of what you have?

[myjeep]

231c and lp dana 30

[4.3LXJ]

I am not sure where you got your info, but that is bassackwards. It looks like you have your pinion just about right for the single U joint. If you wanted a straight shot, it could come up about 2°. So if I understand you correctly, they couldn't get the proper yoke for your 231C?

[myjeep]

correct the driveshaft company said its easier to go jeep to jeep than jeep to chevy. i have what they call trick joints for the jeep driveshaft to gm transfer case and jeep rear axle to chevy driveshaft. and the ujoints are greasable which i don't like at all.

[4.3LXJ]

Did you put an SYE on the tcase?

[myjeep]

no.

[4.3LXJ]

Generally when someone does the double cardan U joint, they do a slip yoke eliminator also. Going to this arrangement, you can get the proper flange for your double cardan. I haven't researched any kits for the S10 tcase, but parts do interchange between the 231C and 231J. You might want to check that out. Then you can do it right and you will be much happier in the end

[myjeep]

sye is for the rear. what i am asking is all about the front driveshaft.

[4.3LXJ]

The usual set up is on a Jeep is there is a front yoke that accepts the double cardan joint. Those are available aftermarket or used. What are you using for a front end?

[myjeep]

transfer case end is a trick joint for jeep driveshaft to chevy transfer case.

axle end is dana 30 low pinion with a yoke for the cardian joint.

at 5mph in 4wd i have vibrations. any faster and it goes away 2wd no vibrations

[4.3LXJ]

I need to see some pics of your angles and how the driveline is in

[myjeep]

pics

1. pic from transfer case

2. driveshaft angle

3 front diff angle

[4.3LXJ]

You should take the front diff angle off the pinion yoke, or top of the ball joint. But, it looks like from your measurements that you have a 4° difference in the angle of the driveline and pinion. That is the maximum you can have and I suspect that if you got a better measurement you would have more. That will cause a driveline vibration. I don't know if you can adjust that or not, but if you can't you will need some adjustable upper control arms to do it

[myjeep]

my uppers are adjustable so i can.

[4.3LXJ]

OK, so here is a balancing act you will have to address. Castor angle vs pinion angle. Ideally, you should have 5° castor angle. But you won't get it with a low pinion diff. So you will have to split the difference, say 3° pinion angle difference and whatever you can get on castor. Do not go to a positive castor angle. It will mess with your steering. The more castor angle you can retain, the better.

[myjeep]

transfer case 5* pinion yoke 8* caster is 9* drives straight now and no vibration in 2wd and a little in 4wd but it still dry out in chicago. did find out the driveshaft was out of phase so i pulled the 2 halves apart and put the ujoints in phase still a little at 5 mph then goes away faster or slower. all in all its alot better and ill see when the snow flies if there is still a vibe or not. the ujoint is almost maxed out at the transfer case, there is about 3/16 to 1/4 inch of space. dont like that to much.....

need to find out what series the chevy u joint is so i can find a yoke for the transfer case so i can flip the driveshaft the corect way. i found the jeep series is 1310.

thanks for your help.
andy

[4.3LXJ]

If it helps, you could use 5° castor. That is the factory spec. I have mine there and I don't need a steering stabilizer

[myjeep]

got the 5* caster and 9* pinion and alot smoother ride but i think having the cardian joint at the pinion is giving me a vibration beeing heavy on that end. still have the slight vibe in 4wd but ill have to see if it goes away when it snowes. it is alot better with more pinion angle

[4.3LXJ]

You will get it dialed in eventually