Not a Noob, but a Noob question:

Sparky-Watts · #1 (**permalink**) 06-19-2004, 07:14 AM

I've been wheeling for almost 20 years now, but haven't really ever talked about it with anyone that knows much, so obviously when I came to these forums, it took me a while to get the jist of some of the terms used. There are still some I don't have a clue about. My question of the week is this:

What is SYE? (Told you it was a Noob question). I've looked around here quite a bit, but can't seem to figure it out on my own, and can't find any threads to explain it. So, what does it stand for, what does it do, and why would I want it? (Not that I really want it, just curious, so I have more understanding when I read about other people using it)

Thanks for your patience and understanding....I will now return the forums to the professionals for an answer!

Tug-n-pull · #2 (**permalink**) 06-19-2004, 07:38 AM

Slip Yoke Eliminaator. see off road glosery! <<< over ther and up a bit. Dude I am just glad you have the knowledge to ask for answers casue we as men get such a bad rap for not asking. I ask directions read directions and look stuff all the time. As an auctioneer I have sold stuff that you would not believe. I have to try to look knowledgeable and present every item as factual as posible to the public. So over the years I have learned it is not that you have to know everything "cause no one does" you just need to know enough people knowledgeable in enough areas to help you look like you know everthing! hehe tug

GreenReaper93 · #3 (**permalink**) 06-19-2004, 07:39 AM

SYE = Slip Yoke Eliminator. It replaces your slip-yoke rear with a fixed yoke. When you get an SYE you'll need to get a CV shaft. With an SYE/CV shaft combo you can eliminating possible vibrations and the transfer case drop. SYE's also give more room for the drivshaft (meaning it can add length to the driveshaft, making it easier to install higher lifts without binding to CV driveshaft.)

Did I miss anything guys?

Joopin · #4 (**permalink**) 06-19-2004, 09:07 AM

Since the sllip yoke is removed and replaced with a fixed yoke, there has to be a "slip" somewhere else. That is also where the CV or constant velocity, driveshaft comes in. In addition to it having a PAIR of ujoints at one end to promote steeper driveline angles, it will have the slip in the middle of the shaft as well, one that will not pull out like the stock set up.

Utah_jeepster · #5 (**permalink**) 06-19-2004, 11:19 AM

Yes that is a SYE kit, but why ? well as you lift a jeep the angle from the rear out put shaft (transfer case) and the differential increases.
A stock drive shaft is made to slip in and out of the transfer case allowing for the minimal flex of the rear end.
Bigger lifts increase this travle ( and increase that angle), once you attain a certain height the travle is too much for this stock set-up and you can pull the rear drive shaft out of the transfer case at extreame flex or what usually happens you start breaking "U"-joints.
The SYE kit comes complete (depending on MFG), it replaces the transfer case shaft and out put housing. It is a simple ,follow the directions install for those shade tree mechanics. You simply install it and at the same time order a new rear drive shaft for your lift.
The biggest diffrence is the rear drive shaft, it has double universal design in the upper end giving you better laderial angle movment. It also has a CV(constant volocitiy joint) in the center of the shaft. Its in and out movement is greater than the old stock slip yoke set-up thus allowing more flex.
It is recomended after 2.5 inches of lift or greater...but I know some have gone as far as 3.5 before installing one.

TwistedCopper · #6 (**permalink**) 06-19-2004, 01:00 PM

I had 4" of lift on a YJ with no problems. 4" is the threshold for "needing" one on a YJ, over 4" of lift makes vibration and damage far more likely without one. I guess each model/year/drivetrain are different.

Joopin · #7 (**permalink**) 06-19-2004, 08:41 PM

Snittys friend BBJ did a spring over axle without a sye!

TwistedCopper · #8 (**permalink**) 06-19-2004, 09:21 PM

Yeah and White tells me that StinkyCheeseman did the same. What year was BBJ's? Just curious because Stinky's is an 87 with the NP207 TC. I wonder if that is a factor, but I would think probably not.

I'm sure that anything over 4" will be tough on ujoints and output shafts without a SYE, but it doesn't mean you can't get away with it for a while.

dick_wilderness · #9 (**permalink**) 06-20-2004, 12:25 AM

Good question!!!!

here's pics of mine:

Sparky-Watts · #10 (**permalink**) 06-20-2004, 01:08 PM

Great! I sure appreciate the answers. It's been bugging me for a while, not knowing what it was. I knew pretty much what it was, just didn't know that's what it was called. Since I probably won't go over a 2 1/2" lift on my YJ, I doubt I'll get one right off. If vibes and u-joints start to be a problem, I can always add-on later, right?