DRIVESHAFT ANGLE

[1tuffcj]

HI i'm new here, i have a 79 cj5 with a 401/727t/fdana 20. with a 4.5 R.E plus M.O.R.E. shackle reversal and 6" shackles. my question is i have pretty insane angle in the rear, i talked to tom at tom woods. he said to put 12 degree shim in the rear right now it's at 14 degrees so with the shim the pinion will be 26 degrees. my output shaft angle is at 8 degrees. what would you guys suggest or has anyone done this kind of angle before.thanks in advance. i was talking to the guy who answered the phone at bulltear and he said theirs a guy who has a driveshaft that messures 9" ( kev ). i also see that fuzz401 is here exccelent.

[fuzz401]

my drive shaft is right around 22 deg but I did not use any shims I cut my spring perch off and lined the rear up and rewelded them back on

[tufcj]

Is the rear shaft just standard u-joints or CV? For standard U-joints the pinion and output shaft of the t-case should be about parallel. If it's a CV, the pinion should be about 2 degrees below a straight line with the driveshaft. The long shackles will already have turned the pinion up some.

I run a t-18 and scout 300 with a SOA + 2" lift (about 7.5" total lift). I run a CV rear shaft. My rear pinion is turned up about 18 degrees.

You'll probably want to overfill the rear a bit to make sure the front pinion bearing gets enough lube.

Bob
tufcj

[1tuffcj]

shims are fine right, thats what the guy was saying at tom woods, they are steel.

[tufcj]

Shims are fine, steel are the best. It would be even better to cut the pads off the axle tubes and re-weld.

Shims that thick will probably require new centering pins since they are usually cut off flush with the nut, and the head won't be tall enough. Make sure they still engage the axle pad solidly, or the ride could get interesting.

Bob
tufcj

[1tuffcj]

thanks. whats a good gear oil to use? the guys at dynatrac said not to use synthetic. they said gear oil plus additive. i have tru trac in the front and lock right in the rear. thanks. 1tuffcj

[tufcj]

Since both the Truetrac and Lock Right are mechanical, no friction modifiers should be needed (those are just to make clutch-type posis smoother).

I don't see why a synth would not be recommended, except for cost. I just use a good quality 80W90 in mine, and change it yearly, or when I've been in deep water.

Bob
tufcj

[KEV]

Yes my rear driveshaft only has 2" if tubing on it but it has a CV and a slip on it also. I also have a Currie HP and my flatty doesn't have a very tall stance. It also has radius arms in the rear with a center limiter strap.

I dont have a diggi camera to take pic with but MC might have some photos of it.

If you do MC and you post them, thanks, thats more beer I owe you.