jwe2

So I've had a 2" lift on my XJ for about six months now and I have a very slight vibration at around 25mph which was not there before the lift. I attribute this to the drive shaft angle at the transfer case or at my rear diff. not sure which but it is insignificant enough for me to ignore. could be u-joints too I suppose, i dunno.

Anyway, I'm planning on getting a 4.5" lift very soon and I am not 100% sure if I need to spend the money immediately on a SYE and cv drive shaft. The reason I wonder is because the 4.5" kit I'm looking at includes transfer case drop spacers. I'm guessing they think the transfer case drop is supposed to take care of the vibrations? Why else would they include it in the kit? This also makes me worry because if I have slight vibrations at 2" of lift, how could it get any better at 4.5" of lift with a mere 1" tc drop?

I plan on getting a SYE eventually anyway, but if you guys think the tc drop included in the kit will suffice for now, it would be a lot easier for me to wait and spend the money on the sye later.

btw here's a link to the kit:

http://store.fatbobsgarage.com/jeep-...001-p7849.aspx

(it's the one with full leaf packs so don't hate )

Thanks guys

gvns8

Not sure what your exact question is, but I always do one thing at a time. Then if something goes wrong you know what causes it.

In regards to the lift, you can also shim the axle in the opposite way people normally shim it for an sye. Also vibrations due to lift/lack of sye usually get worse the faster you drive so your current problem sounds more like a u-joint gone bad.

Soo I would fix the current vibration...then install the lift... see if it vibrates... if yes then try the shimming... then maybe a larger tc-drop for a band-aid... then the sye as soon as you have the money...(you can get an sye for about $150 if you get the Rubicon Express Hack n tap and just pick up a regular old front drive shaft off an xj through either ebay or the junkyard- it will be just as strong as stock setup and the front drive shafts are stronger than the rear stock shafts just fyi). Good luck!

jwe2

hey, thanks for the reply! I'll have to look into the u-joint issue right away to see if that helps. u-joints are cheap in comparison to a new drive shaft and sye lol. I'm only attributing the vibration to the lift because the day before installing the lift I had no vibration at all.

I can afford the lift and sye at the same time, it's just that I can think of numerous other things to spend that money on first if it's not necessary immediately.

jwe2

Is it very common for people to need an SYE with lifts up to 4 or 5 inches?

dpace7XJ

Might have a bit of vibration, but i think you could get away with it..ive run a 6" lift without an sye for 2 years and haven't hat a problem yet, just a slight vibration but an sye kit is definitely on the list. I had a 3 inch lift before, and had zero vibrating, so my guess is you would be okay

jmm0122

Before you order from fat bobs I would pm grimus99xj. He is a RC vendor on this forum and he offers a forum discount and free shipping to all members. It might save you a few bucks, shipping tends to be expensive. Plus ordering directly from the manufacture is always better than going through a middle man.

jwe2

thanks for the info, I'll definitely look him up when I buy the kit. In the mean time I'll pick up some new u joints and see if that stops the vibration.

Roughcherokee95

Well, with everyone speaking of SYE & going to a 4.5'' lift..

I have a 3'' Rough Country lift right now, with little vibrations...
and i want to push it up to 4'' with Coil spacers and shackles.
Will i need to run a SYE and a longer Drive Shaft?

clayton3854

at 4.5" you will most definalty have vibrations from your tcase and the angles of your driveshafts. occasionaly just a tcase drop kit will work but you tend to still get vibrations theres. my suggestion would be to spend the money on an sye and if your jeep is automatic then you can just use a stock auto front driveshaft as your rear shaft for the time being while you save for some driveshafts. you will get vibrations here but not until 65+ mph with a tcase drop you should expect vibrations around 45 mph.

Jeepxj1234

Sorry to butt in here but when you use the front drive shaft with a SYE I heard you had to get it legnthened or something? How do you do that?

clayton3854

you dont HAVE to get it legnthened or shortened it is reccomended for the least vibrations but i didnt do either to mine and it fits and runs fine. iv been looking into and asking around about using both stock shafts when i upgrade to my 6.5" lift and from what iv gotten so far i think im gonna take that approach as well until i can save up for some tom woods shafts

Jeepxj1234

Alright thanks

jwe2

I'll be installing the 4.5" lift sometime this week hopefully so I'll post when I find out if I get much vibration or not.

I should probably just wait to install it because if the vibes are really bad and I need to order the sye, I'll have to leave my jeep garaged for a few days while it ships. I have zero patience though when I order something new lol

It seems like the question of vibration or not with certain lifts is all dependent on the individual vehicle. Some of you said no vibes with 6" and others said possible vibes with 4.5", definite vibes at 3", etc etc. I'll just have to see after I install it I guess.

jwe2

alright well I decided last night to just order an SYE and driveshaft kit from Iron Rock Off Road since their hack-n-tap and refurbished xj front driveshaft package was only $200. I figure this will save me any headaches and waiting if I do end up needing it. Plus I'm giving my current 2" lift to my brother for his xj and that way he can have the tc drop from my new lift kit if he gets any vibes (his is a 97).
I also got some rear bar pin eliminators. the clunking noise from my shocks in the back is annoying as S$%.

I think I'll turn this into a build thread and do a nice write up/pictures of the install of the lift and sye together. Luckily my grandfather owns a machine shop so I'm going to just remove my rear output shaft on my tc case and have him cut and tap it so that it is cut exactly even and the threaded hole is perfectly centered.

I guess I should rename this if it's turning into a build thread, huh?

edit: is there a way to rename a thread? nevermind I'll just start another one called "94' XJ 4.5" lift/SYE Build"