SYE or Longer Driveshaft

[Louder]

I've been researching going higher than my current 2" in the future. To do things correctly, I determined I need to get my driveline upgraded before lifting.

After talking with local XJ owners about the SYE upgrade. I was told they hadn't done it. I was quite surprised since the average lift in their XJs was about 5"!

They told me that they had lengthed their driveshafts by about 2" and had no vibrations at all.

Is this another option other than SYE?

Thanks for the help,
Louder

Oh yeah, for those that read my previous post... a front end alignment took care of my DW..

Thanks guys!

 

[ChuckD]

Please give us some specs on your XJ again, Year and tcase, transmission?

 

[Louder]

Sorry about that, my XJ is a 01 Sport. 231 T-Case and I'm not sure of the Trans ID but its an Auto w/ OD.

The other XJs were all 98-99 Sports with basically the same equipment.

 

[Eagle]

The '96 and newer XJs have a transfer case with a very long, unsupported transfer case output shaft. This is why even mild lifts usually cause vibrations with the newer XJs. When you lift, you increase the angle between the transfer case shaft and the drive shaft, and the increased angularity causes the output shaft to wobble and whip around.

A longer drive shaft will address only one problem -- the slip yoke falling off the output shaft. It does nothing to correct the increased angularity. Even if you don't feel vibrations, the u-joints are operating at close to or beyond their recommended limit, which results in rapid wear and frequent replacement. More important, under heavy loads (such as rock crawling), the eccentricity on that long, unsupported tail shaft can cause dramatic and extensive failure.

All that having been said, I suppose it's possible that you might get away with no SYE if you do only mild wheeling. Personally, I would not risk it. I stand behind that so fully that I have an SYE waiting to go into my 2000 XJ, and the only lift it has is factory Up Country suspension. The new transfer case design is, IMHO, a disaster waiting to happen.

 

[Louder]

Thanks for the quick response. It makes a little more sense now. I'll probably just save up some money and get a good SYE before I consider lifting anymore.

Again, thanks for the great input.
Fred

 

[Bentonedge]

so are you saying that it is easyer to get away with a biger lift on the older jeeps. like an 88?