hey, i just got a 98 xj with a 6.5 rough country long arm lift with 33in BFGs and when you accelerate or at crusing speed theres a nasty vibration (worse if you relly get on it) i went though and all the cv joints are good the slip yoke dont seem bad wheels are balenced.. any ideas?

 

Sounds like you driveshaft angles are too harsh.

 

Get a slip yoke eliminator.

 

yep, these guys are right on track, at that height and still running the stock slip yolk, you probably have driveline vibes due to bad driveshaft angles. Get an SYE.

 

Or a HnT (hack n tap) which, IMO is better.

 

Alright thanks guys

 

I talked to Tom Woods custom DS's today and they wont warranty their DS with a H&T

 

That's annoying. Did they say why? And how would they know exactly?

I still say the HnT is better. If you nuke a tcase you may ruin the SYE. With a HnT you can almost always move it to the new one.

 

Well I was up front then I was pricing, they ask what type tcase and method of attachment and this is what they told me. When H&T's started coming out and still do have balance issues which would cause vibes. Tom Woods for a period would not make you a DS if he knew you had one. Well I guess they started again but the reason they wont warranty is vibe caused by H&T can ruin the double cardan joint quicker. They also recommend their HD SYE kit or similar because theres an additional roller bearing to support the weight of the DS. plus true SYE kits have larger spline count for yoke

 

what I read from that was that he wants to sell you his slip yoke eliminator along with his driveshaft

I find the spline comment weird because what they have listed as their standard shaft, (the S spline stub shaft) actually has quite a bit less spline engagement than a stock slip yoke shaft and even a pretty good amount less than my hack n tap

FYI several thousand miles later and my HNT has no vibration issues...there is no reason that a HNT should have any more vibration than the stock slip yoke unless the splined yoke you buy is not the correct part

 

^ yeah I said screw it and started rebuilding my DS for fit my application. Napa is awesome and actually carries the things needed to rebuild a double cardan joint