My son has been driving my '91 YJ and he is going through a set of rear
U-joints a month. I've tried regular greasable, super duty through cap
greasable and even the extra heavy duty non-greasables. The lift is only
2", running 31s on 3.07 gears. I've replaced the dif yoke. I know he's
your typical lead-footed teenager, but even that does not explain the
short lifespan. Any suggestions?
--
jeff

I would guess the angles may be off so it is vibrating around 60 mph.
This shake can destroy them.

I eat more rear ones than I should with my 3.5" lift. I have a proper
2.5" spring lift and YJ shackles that lift one more inch. The shackle
lift has put the angles off on my back yoke. The face of the yoke
coming out of the t-case is supposed to be parallel with the face of the
rear end yoke.

This means they look something like: =| |= or if the t-case is
tilted down, =/ /= .

Sometimes folks put the rear yoke pointing toward the t-case too much.
Mine is something like: =/ |=

Folks use an angle finder to match them up.

The other nasty one is the end tabs on the yoke. If those tabs aren't
perfect, the u-joint can slide end to end slightly. This will wreck
them fast.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

jeff wrote:

Mike should have explained that the shake is really not a shake, it's a
bind. The bind makes the driveline shake, and it't the bind that destroys
the joints. His diagrams, =| |=, =/ |= , etc are right on.



"Mike Romain" <romainm (AT) sympatico (DOT) ca> wrote

I've never seen a so called "super duty" universal joint as strong
as the standard Spicer, the book calls for. By now your clutch should be
worn to the point your Son can no longer get second and third gear, so
the new set should last the normal fifty thousand for that angle.
God Bless America, ßill O|||||||O
mailto:LWHughes3rd (AT) aol (DOT) com http://www.billhughes.com/

jeff wrote:

Unfortunately we're only about 8000 miles in on a freshly rebuilt 4.0
with a new clutch.

L.W.(ßill) Hughes III wrote:

L.W.(ßill) Hughes III wrote:
You do lead a sheltered life now don't you Bill. But then since you
haven't been an active offroader in many years, that you don't know
about them doesn't surprise me.

Jerry
--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/

Jerry Bransford wrote:
Ah you desert rats are just lucky you can use those sealed POS'es, they
get contaminated with water way too fast up here in the muskeg and
swamps. Our mud burns.....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

What's your problem, Jerry? I'm probably out there more than you, at
about once at month. A few of the pictures I've taken of my Son while I
was there at: http://members.aol.com/LarrHughes/index.html
I've probably forgotten more about four wheelin' and machines than
you'll every learn.
God Bless America, ßill O|||||||O
mailto:LWHughes3rd (AT) aol (DOT) com http://www.billhughes.com/


Jerry Bransford wrote: