there is NO way you can answer this question

[00xj]

Go ahead tough guy, give it a try.



1. Read this thread.
http://www.naxja.org/forum/showthread.php?t=14240


2. I replaced both bearings for the output shaft,
(the one that controlls the front-drrive shaft)

3. vibe is less, but still there. The more I press the gas the louder it gets. only there in 4wd, couldn't take it on the h-way, it's snowing like crazy here right now, (Mich)


well what have you got to say about that?

Thanks, Tom

2000 XJ +3.25, 31's, 242t-case, lift included lower arms, front shaft has all new u-joints and slip yoke, balanced, centering yoke is operating fine, no componets stearing changes, ?????

[Georgia Mike]

I'd pull the case and check the tolerance on the thrust of the shaft. Sounds like the case may be worn allowing the shaft/bearings to move either back and forth or side to side AKA:"wobbling" in a sense. This would definately cause vibes. Were the vibes there before you did the SYE? Another thing to check for might be the front pinion angle. The 00's use a low pinion 30,correct(at least my wife's does)? Is your rig lifted(I'd say so with an SYE)? It's possible to not have the vibes under normal driving conditions and have them start up when the driveshaft is under power. Just my $.02 :D

[00xj]

I'd pull the case and check the tolerance on the thrust of the shaft. Sounds like the case may be worn allowing the shaft/bearings to move either back and forth or side to side AKA:"wobbling" in a sense. This would definately cause vibes. Were the vibes there before you did the SYE? Another thing to check for might be the front pinion angle. The 00's use a low pinion 30,correct(at least my wife's does)? Is your rig lifted(I'd say so with an SYE)? It's possible to not have the vibes under normal driving conditions and have them start up when the driveshaft is under power. Just my $.02 :D


Thanks Mike,
I just edited the 1st post to include my lift info. I have a low pinon front.
65K miles? Worn Case? When I put the two bearings in they were very tight in the case, the dealer did the rear one and said it was fine, I had to firmly tap the new front one in, does that change your thoughts?
I can yank on the front yoke and it's rock solid. There is a slight"bump" from the CV, but man it's microscopic, heck it's got all new joints!! I guess all that's left is to have the centering yoke replaced and rebalance that shaft??

I wish I never lifed it.

[Georgia Mike]

I wish I never lifed it.
Aww,come on now! In the situation that you describe,I'd check the C/A bushings and pinion angle. What kind of arms are you using? Where they new or used when you bought them?

[00xj]

Aww,come on now! In the situation that you describe,I'd check the C/A bushings and pinion angle. What kind of arms are you using? Where they new or used when you bought them?


New arms, this summer. Black Dimond 3in kit. not adjustable, stiff bushings (poly?)

I'll go measure the pinion angle.
Well,
axle is 10 degrees (as measued on the largest portion of the tube)
pinion is 6 degrees
(as measued off the flat spots on the tubes by the diff cover)

as always, THANKS

[00xj]

Mike got me thinking, Pinion angles. never thought of that,(I kinda thought that was just a rear thing) so I did a search.

Did MaxJohnson have it right in this naxja thread (#8) (http://www.naxja.org/forum/showthread.php?t=3050&highlight=front+axle+pinion+angles) ?

My last alignemt numbers were

Left front camber -0.5
Right front camber -0.9

left front caster 6.1
right front caster 6.2

left front toe .03
right front toe .11
total toe .14
steer ahead -.05


learning every day,


(Oh, I take back the "should never lifted it comment, my bad)

Thanks

[Lincoln]

I'm too lazy to read much right now so I'll just answer. :)

I angle of the pinion in numbers doesn't mean a whole lot. Make sure the pinion yoke is pointing at the yoke on the driveshaft. The general rule of them is 1 degree down from a zero angle at the axle end. I've varried a few degrees on most without any problems. Your goal should be to get the angle in the axle end U-joint zero degrees.

You can change the shims on the body end of the lower control arm to adjust the pinion angle. Just a guess, but I bet with 6 degrees caster your pinion is pointed a little low.

[jeepme]

My front end is at 6 deg. with the warn hub kit. If I lock the hubs my vibes start at about 40 mph and get louder and worse the faster you go when in 4wd. In two wheel drive with the hubs locked it starts about 60 mph. I would definately look at your pinion angle.

Jeff

[Nay]

The driveshaft on a 2000 XJ spins whether it is in 4wd or not. My guess is you have some cyclical vibes at about 80 mph, if you ever drive it that fast, in 2wd, and then the heavy vibes in 4wd at 35-40 mph as you describe. That's classic driveshaft angles. Pinion has to be pointed even with the driveshaft angle, maybe a degree below. If not, you will get harmonic vibration from the single u-joint on the axle end being out of phase (it needs to run as close to a zero degree operating angle as possible).

Fix the angles and money says it goes away. I had horrible front driveline vibes for a long time and it never fragged the case bearings...somewhere around 5.25 degrees of caster should fix the problem...

Nay

[ChuckD]

The driveshaft on a 2000 XJ spins whether it is in 4wd or not. My guess is you have some cyclical vibes at about 80 mph, if you ever drive it that fast, in 2wd, and then the heavy vibes in 4wd at 35-40 mph as you describe. That's classic driveshaft angles. Pinion has to be pointed even with the driveshaft angle, maybe a degree below. If not, you will get harmonic vibration from the single u-joint on the axle end being out of phase (it needs to run as close to a zero degree operating angle as possible).

Fix the angles and money says it goes away. I had horrible front driveline vibes for a long time and it never fragged the case bearings...somewhere around 5.25 degrees of caster should fix the problem...

Nay
I agree, I have a TJ D30, the same as 00XJ. I have 4 degrees of caster with roughly 6.5" of lift and the pinion angle is good and steering is very tolerable. Your alignment shop may not want to do this though so you may try to find a HP D30 to swap in or try adjusting the caster yourself.

[00xj]

Well, guess what................................


My lower arms are max'ed out to the rear so I can't adjust them. The control arm bolts are 16in on center.

Now What?

I wish I still had my stock arms. rats.







Max had a good suggestion, he said my receintly replaced pinon bearing could be failing, but even if it was 100% o.k. wouldn't my poor pinion angles still make some vibes? and I cant back my arms up to correct it

the nightmare continues

I told you there was no answer, the lift is comming of next week. Watch the for-sale post for some great deals.

[grasseater]

I told you there was no answer, the lift is comming of next week. Watch the for-sale post for some great deals.

What? Take off the lift and sell your Jeep just because of a little vibration?

Stick with it dude, you'll figure it out. Besides, once you get it right you'll be able to help the next guy. This is how we get better... :doh:

[00xj]

[QUOTE=grasseater]What? Take off the lift and sell your Jeep just because of a little vibration?
QUOTE]

Little?? I wish, I would say it is unuseable. I'm now forced to drive my kids 87 ford f-150, that's pretty embarassing. not to mention I'm making payments on something I can't drive.

[Lincoln]

Why don't you take the front driveshaft out and see if that takes care of the problem?

At least you could drive it and see? If that is the problem it will give you time to figure out how to fix it. I would definately do that before pulling the lift.

Do the '00's adjust caster like the TJ's? Cam bolt at the axle end?

I can't help much on the length, it's been a while since I had anything that was comparable to stock.

I would be tempted to run without a front shaft long enough to save a few bucks for some adjustable uppers. My only reason for doing the uppers is to get rid of the stock arms. Then when the bushings go in the lowers replace them with an adjustable set.

Aren't big boy toys fun? :D

[00xj]

Why don't you take the front driveshaft out and see if that takes care of the problem?

At least you could drive it and see? If that is the problem it will give you time to figure out how to fix it. I would definately do that before pulling the lift.

Do the '00's adjust caster like the TJ's? Cam bolt at the axle end?

I can't help much on the length, it's been a while since I had anything that was comparable to stock.

I would be tempted to run without a front shaft long enough to save a few bucks for some adjustable uppers. My only reason for doing the uppers is to get rid of the stock arms. Then when the bushings go in the lowers replace them with an adjustable set.

Aren't big boy toys fun? :D



Yea it runs great w/o the front shaft, I ran it that way for a few months. The arms are adjusted by loostening/tighting a pair of bolts in the C/A bracket, these bolt move a asssembly that moves the c-arm fore and aft.
I can't put any more $$ into this Jeep, it just doesn't make sense anymore, I don't see an end to the spending.

[grasseater]

I can't put any more $$ into this Jeep, it just doesn't make sense anymore, I don't see an end to the spending.

J-E-E-P

Just Empty Every Pocket... :cheers:

[00xj]

J-E-E-P

Just Empty Every Pocket... :cheers:


Exactly!! :)

I am going to take the front shaft off, drive it like it is and let my brain cool off for a week or two, then I'll think about it again.

A wise man once told me
"The worst decisions are made when your frustrated and pissed off."

and I'm both.

Thanks for reading this thread.