Front DS Vibes with 5"

I'm running 5 inches of lift and have vibes due to too great of an angle b/w the pinion and DS. Does anyone have this problem? I have a CA setup for 4.5" of lift, but the caster angle would only be affected by a couple degrees when the difference is something like 10*.

And i don't need any more about flame about how my angles are fucked up and that i need the right CA lengths to be safe... I KNOW! It's safe now, drove it over 1000 miles and it's fine for now. I just wanna know what the deal with the pinion is before I do anything else.

The problem is your LP axle,youll have to compromise between castor and pinion angle.I chose to try to get as much pinion angle as possible,meaning I run about 3* castor at 6" lift w/ a LP D30.

simple solution is to run without the front shaft installed. when you hit the trail just take 5 extra minutes to slap it back in when you air down. then start thinking ahead to an HP axle and your next upgrades

got ya... so where would i get a HP and how much would that run me?

And what's the diff b/w the HP and LP, is the pinion just rotated upward more on the HP?

I mean, i'm running no front DS now so I guess that's how I'm gunna do it from no on.

95+ through 99 XJ Front ends will all be considered beneficial swaps for your application. They'll be high pinion and they will be non-disco with the larger size u-joints.

so i got the poo with the 2000????

2000 and 2001 XJs just come with low pinion d30s. Fine for stock, but when lifting, the high pinion front end is more beneficial due to the driveshaft angles.

DAMNIT!!!!! So if I swapped out the one i've got for one from a 95 to 97 it would most likely reduce the angle to where there would be no vibes?

anyone got a picture of the HP30?

Not the best pic but it shows the pumpkin enough you should be able to see the difference,its out of my 95!

gregmondro said:

95+ through 99 XJ Front ends will all be considered beneficial swaps for your application. They'll be high pinion and they will be non-disco with the larger size u-joints.

Click to expand...

even if he gets a 91-94 HP3o he can swap the shafts from his 30

just replied to your other thread. Changing the axle might help, but after reading my other post, I have a 94 (which is HP) and still have the same problems you are.

here is my HP D30 out of a 95, so it has the x297 joints

You just wanted to show that disgusting ass thing off

obviously j/k looks sick!

Is that the TnT truss? I like! How hard was it to cut your UCA mounts off?

I ran the 5.5 inch TNT lift on a stock 2000 lp30 and had no vib's. Be sure your drive shaft is good. Take it off and drive it, See what happens. The ujoints in the double cardan joint can appear to be ok, but if the centering ball and socket are worn it will wobble. It should not be hard to rotate the joints but it should have sort of a tight spot when it is at full bend and its rotated. Its hard to explain. If you had good and bad shaft side by side you would see the difference. The double cardan isnt just two joints side by side. Its also critical that the centering ball is tight or even new joints are no good. They have to be supported by the centering ball and socket. Some times its bad enough to mess up the transfer case. I drove mine on the eway with the lp30 and it was fine. I now installed an hp 30 only to gain more rock clearance. I also know I messed with it a lot to get the caster set up right. I don't know the numbers right off. Its been awhile. When I put the hp30 in I had to do it all again. I just picked up a junk transfer case because the guys front shaft blew apart at the d cardan joint. It broke the tc in half. Another guy I know had bad vib's and his front shaft was wasted. Measure twice, cut once.:cheers:
I will get a photo of the "good" front drive shaft. I ran across one with the grease holes in it. It uses the small needle type grease gun to lube both the joints and the centering ball. I know my 2000 shaft isnt made like that.

rosco said:

Is that the TnT truss? I like! How hard was it to cut your UCA mounts off?

Click to expand...

yep its the TnT truss, cutting off the old UCA mounts was a breeze. i used a 4.5" grinder and the cast iron one over the pumpking was the easiest to get at. the passenger side was a little more difficult because u have to cut off the old trac bar mount, and clean that up really well, but its actually not bad to install.

the only tip i have on install, is to weld really slowly so that the you dont warp the housing.

In your original post you say that you have the arms for the 4.5 inch lift. I see some of your other posts you mention different lenght arms. If thats the case it ccould be that your pinion is way off. You do need to get it half way close. I assumed you where in the ball park. It shouldnt vibrate if your close. We need to go back to square one to figure this out. It would be a lot cheaper and easy to get the arms right. Do you have an angle gauge?

i got the jeep aligned today and they gave me a printout with the angles...

left front caster: 7.94*
right front caster: 7.66*
cross caster(whatever that is): 0.28*

if any of that helps... I think I threw an angle finder on the front really quick one day and it said 0* but I can't say for sure how accurate that was. But if you think about if I had the appropriate arms for my lift it would change the angle by maybe 2*...

Drop brackets would help but get some adj uppers for sure,You can gain alot of pinion angle based on those numbers!