zimms 76 work

[pghfj40]

The length of the DS could be a factor There is nothing you can do with that.

One more thought: the length shouldn't matter unless there's so little insertion (snicker) in the slip joint that it's causing slop radially.

Presumably he's at static ride height at 40+mph (unless he's Baja'in it! Yee-Haaa )... if so this'd be bad: it will fall apart during droop. (Not really even safe for street).

 

[78Crusher]

0 lift 5 speed tranny tiny DS

 

[Zimm]

the dude measured the shaft phase with the reweld. said it was a high quality job, and doubted it was out of balance even though he didnt have toyota plates for his balance machine.

so...

took it to pgh drive line yesterday. said it "slightly" out of balance (corrected that) with no other issues. said the amount it was out wouldnt have been noticeable in a 4wd rig. look elsewhere for the culprit.

so...

thats two DS guys. the DS is definitely ruled out.

 

[pghfj40]

what are the three angles?

 

[Zimm]

i dont have anything to measure that.

 

[pghfj40]

i dont have anything to measure that.

Magnetic Angle Finder: <$10 @ Home Depot or you can borrow mine

see one in the links below:
Driveline 101

http://www.4crawler.com/4x4/CheapTricks/Images/Angle01.jpg

 

[Zimm]

theres a 5 degree difference in the u joint angles.

the rear is only .4 deg from pointing directly at the tcase. maybe a CV is in order.

 

[pghfj40]

theres a 5 degree difference in the u joint angles.

the rear is only .4 deg from pointing directly at the tcase. maybe a CV is in order.

It should be cheaper to just modify the pinion angle...

If there were more angle on the shaft, that would justify a CV, but 5* on each joint in a two joint shaft isn't bad (if I'm understanding you correctly: the tcase/ebrake is pointing down @ 4.6*, right?).

New spring seats/saddles are $20 from Mopar... plus a small bit of time grinding/welding. Rear axles are easy.

New CV's are BFn expensive, especially if you plan ahead to make sure it handles the angle needed during droop for whatever suspension you eventually intend (most stock cv's bind at pretty low angles)...

you can get em with up to 45* tho

(maybe more, now?)

HTH. -Ed '70FJ40

 

[pghfj40]

PS--Before grind/weld, as an experiment to confirm changing the pinion angle would fix the vibe w/ existing shaft...

Point the pinion down with 6 or 7 degree shims... prob only worth it tho if you find em free/cheap. Suggesting *only* as a temporary test.

BTW I say 6 or 7 degree because the pinion will wrap upward a bit under power... bringing you back to your ideal 5 degrees for parallel flanges. Also, as you rotate your pinion down, you'll get slightly more angle at the xfer flange joint, so this new angle becomes the target.

 

[Zimm]

PS--Before grind/weld, as an experiment to confirm changing the pinion angle would fix the vibe w/ existing shaft...

Point the pinion down with 6 or 7 degree shims... prob only worth it tho if you find em free/cheap. Suggesting *only* as a temporary test.

BTW I say 6 or 7 degree because the pinion will wrap upward a bit under power... bringing you back to your ideal 5 degrees for parallel flanges. Also, as you rotate your pinion down, you'll get slightly more angle at the xfer flange joint, so this new angle becomes the target.

i was figuring on ordering a pair of 5* weld on shims, or tying to locate an 82-84 fj 60 front DC shaft to shorten.