Does anyone know why. . . SYE related

Someone recommended to me to just get a custom drive-shaft made with a CV joint and a slip yoke to replace the stock one. Is there some reason I don't about why the slip yoke need to be eliminated?
P.S. I just installed a RE 3.5" see http://www.naxja.org/forum/showthread.php?t=31278
and am now dealing with the drive line vibes. dropped the transfer case which helped 80%, have rear axle shims on order, but still have BAD vibe at speed with 0 torque on drive-line, i.e. go peddle between idle and go.

Chuck

sye does a couple things....

I like them because if you break a u joint.... you can remove the DS and get home (in front wheel drive) with out dropping your lubercant on the trail.

also... It keeps the "slip" yoke from slipping out under extreme flex

I'm sure there are a ton of other reasons I forgot or dont know....

I'm sure you'll see them...

chucknewell said:

Is there some reason I don't about why the slip yoke need to be eliminated? Chuck

Click to expand...

I know this sounds weird but the yoke will actually rub on itself, which cause's the vibes. If you look on your yoke on the drive shaft at the t-case end you will see where it is hitting itselft. Just look, and you'll see what I am talking about.

Anyway, I had the same problems with my RE3.5" super-flex kit. I had to grind down on the yoke on the d-shat at the t-case. Plus I added the 1" t-case drop for a little while. Combined between the two, it solved my problem by about 90% but I still had de-acceleration vibes. Finally I broke down and got the Tom Woods SYE and new CV d-shaft for my 242. I installed that, toke off my 1" t-case drop and I have had no more vibes what so ever since then. It is well worth the money!!

Actually, Chuck's profile says he's got a 98 so leaking fluid isn't a problem if the rear shaft has to be pulled. However, that means it's got the new case which is more prone to vibrations because of the longer unsupported length of the output shaft.

Hack-n-tap or other SYE options shorten the output shaft, which can help reduce vibrations. A longer driveshaft means shorter angles on the u-joints, which can extend their lives. The reduced operating angles also help reduce vibrations

Like Yucca-Man said, being a 98, the Tcase is sealed. So basically for $80, plus the cost of the driveshaft, you can have an SYE. This and the proper amount of shims will take care of your vibes.

thanks for the correction...

Thanks for everyone's input
Chuck