[jmenona]

Hi,everyone
I have a 96 zj 4.0L with 3.5 IRO springs with adjustable control arms etc running 31's. The lift ended up being more like a 4 inch lift. Prior to this I had 2 inch BB for a few years with zero issues. since The new lift I'm having bad front driveshaft vibes at 80 mph. As long as I don't hit 80 its okay. Remove the front driveshaft and no more issues. So, I figured it was my stock shaft since it was fully extended with the new lift. So,I put a tom woods driveshaft on and same issues at the same mph. I have 1 degree pinion angle w/5 degrees of castor. Double checked everything (nut,bolts,control arms, alignment, etc) what could be causing my issues?. I know there's plenty of zj,xjs etc with 4,5 and 6 inch lifts with no front driveshaft issues.is it possible tom woods didn't get the driveshaft balance right or maybe ups dropped it one to many times delivery it to me? I'll give woods a call on Monday. I really don't know what could be causing this because prior to the lift I've had no issues. Any ideas would be appreciated
Thanks

 

[Jeeprat78]

Yeah there is always that possibility that it wasn’t balanced correctly. Have you check your tires
To make sure they’re balanced ok? Or maybe your tire wear is off?

 

[MuzzaAus]

So presumably you have a double cardan shaft?
What is the joint angle at the transfer case? Each uni-joint should not have more than 10 degrees I believe.

If you have Rzeppa joints, get rid of them. I have a double Rzeppa on the WJ and it is coming out, just 2" lift is causing issues.

 

[Goat Guy]

Simple solution; don't go 80mph. But seriously, if by pinion angle you mean caster, I'm thinking Tom Woods is going to say that you need about 4° of caster. At least, that's what they told me back when I was at 4" with my WJ.