SYE Advice

[IH8RDS]

What exactly are the benefits of a SYE?

When you lift a jeep the angles for the drive line are way out of tolerance and causes driveline vibrations. An SYE puts a double cardon joint in the rear to compensate for driveline vibes. Pretty much eliminates vibes. You have to reposition the axel housing to point at the transfer case. You can do it with shims, or more permanently, re-weld your spring perches like I did.

 

[BigAl]

What exactly are the benefits of a SYE?

Also when you break a rear driveshaft, you can simply unbolt it and continue in FWD. If you remove a slip yoke style shaft, the fluid drains out of the TC.

SYEs typically allow for a longer rear DS too.

 

[IH8RDS]

Scott, how many miles on the TC? Most i have done with higher mileage could benefit from new shift mode fork pads.

http://www.quadratec.com/products/52219_01.htm

I re-read that... lol. I have 100,000 miles on my TC.

 

[DaveInDenver]

What exactly are the benefits of a SYE?

I had to look it up, too. Transfer case slip yoke eliminator (SYE, nothing gets past me), right? Having always owned Toyota 4WD trucks I never knew about all this, since they put slip yokes in the drive shafts. Not to sound snobbish, but why the heck would anyone ever think to do it this way? Seems prone to problems on a 4WD vehicle...

 

[jagular7]

Mfrs are always looking for cheaper costs.
Low sitting 4wd vehicles are to be used on the flat paved streets and not for offroad trails.
1-pce driveshafts have simple components to assemble.
Less material requires less balancing, thus less vibrations.
Centerline of driveline (crank, input shafts, pinion) can all be designed to minimize vibrations.
Less maintenance.

Probably among the dozens of reasons.

 

[DaveInDenver]

Probably among the dozens of reasons.

All true, very true.

 

[IH8RDS]

I finally got around to doing this today. I don't know why I didn't do it sooner. 80mph and zero vibes. The PORC SYE was easy to install. I was going to pull the whole transfer case, but after I got under there it was no trouble doing it installed. The stock front DS fits like a glove. For info I have the AW4, 231J and 8.8 rear axle. The benefit of having the same drive shaft speaks for its self. The doner DS has to be from an XJ with a Dana 30 HP with an AW4 transmission.

Like I said I have no idea why I didn't do this sooner. cheers :elkgrin:

 

[ExpoMike]

I finally got around to doing this today. I don't know why I didn't do it sooner. 80mph and zero vibes. The PORC SYE was easy to install. I was going to pull the whole transfer case, but after I got under there it was no trouble doing it installed. The stock front DS fits like a glove. For info I have the AW4, 231J and 8.8 rear axle. The benefit of having the same drive shaft speaks for its self. The doner DS has to be from an XJ with a Dana 30 HP with an AW4 transmission.

Like I said I have no idea why I didn't do this sooner. cheers :elkgrin:

Glad it went well. Yep, in vehicle is much easier then pulling the whole box. Since I did this from day one with the lift and rear end change, I have not had vibs so no idea what that. It rocks to use the same drive shaft front and rear.