PDA

View Full Version : Rear driveshaft vibes after re-torquing sye yoke


srmitchell
April 19th, 2013, 12:10
Hey guys, I installed a PORC sye kit and a Tom Woods shaft into my 01 xj. 33's, 4.56's about 6 months ago.

I had front driveshaft vibes for like 2 years, and I finally fixed all the vibes... it was perfect. Smoothest in 5 years.

On tuesday, I inspected my rear driveshaft and noticed that the sye yoke was totally loose. So I marked the driveshaft/yoke (so I could reinstall it the same way), took the shaft off, tightened the yoke to 150 ft/lbs as stated in the directions for the SYE kit. Reinstalled the shaft, and properly tightened the bolts.

Just took it on the freeway today, and there's a strong droning vibration from 50+. WTF.... I had just fixed this totally. I inspected the shaft and yoke, both look good. Did I maybe over tighten it?

Thanks!

-Sean

VAhasnoWAVES
April 19th, 2013, 12:47
the yoke sits on a splined shaft, right?

if it was loose, it likely wore on the shaft, or the inside of the yoke itself. take it off, if you see shiny metal, you know what the culprit is.

srmitchell
April 19th, 2013, 13:40
Yes. Damn that sucks. I know the shaft is hardened, so maybe I can simply replace the yoke. I torqued it to spec originally, I guess it worked loose. Really lame. Haven't even wheeled it yet.

jwebb85
April 19th, 2013, 13:54
Just out of curiousity, how does the regular slip yoke not wear the shaft?

srmitchell
April 20th, 2013, 10:56
So I actually loosened the driveshaft yesterday, jacked up one of the wheels and kind of tapped the joint with a hammer hoping to seat it better, tightened it back up in an opposing pattern, and the vibes are gone! Such a relief. Thanks for the help guys.

Boostwerks.com
April 20th, 2013, 12:28
Glad to hear you got your vibes sorted out! What did you end up finding with the front DS?

srmitchell
April 23rd, 2013, 10:10
So I actually swapped in a new tcase, it had only 60K on it, and I put the PORC sye in it too. Initially, it still vibrated with the new case.

I put my nicer tom woods shaft in the back, and put my good condition front shaft (that I was using with my hack n tap) up front. I adjusted the pinion angle to precisely zero degrees, and magically, most of the vibes are gone. I can cruise to about 71, then the vibes start. Good enough for me.