Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 9 of 9 Posts

·
Registered
Joined
·
24 Posts
Discussion Starter · #1 ·
Hello!
I could use some help, as I am good working with everything on my jeep except differentials. I have a 99 TJ with a Dana 30 front axle. Ive got a problem where when I get over 55 MPH the jeep vibrates, but when I turn the four wheel drive on, it goes away. I have already had this problem before and I rebuilt my front drive shaft including the double cardon joint and front U joint, and that seemed to fix it. Now its happening again so I crawled underneath to check it out. When I spin the front driveshaft out the yoke comes out about 1/4 inch, and I can wiggle the driveshaft up and down almost 1/4 inch. When I spin the shaft in everything tightens up and I can't wiggle the shaft at all. Do I just need to crank down the pinion nut? Or is it something inside?

Sorry for the long explanation but I wanted to provide as much info as possible.
 

·
Registered
Joined
·
2,321 Posts
is it the yoke that slides around on the shaft or is that transfer case shaft also moving with the yoke?
 

·
Registered
Joined
·
2,321 Posts
i must have misunderstood i thought you meant the yoke of the TC......
your speaking of the front axle pinion and drive shaft at that end?

what shaft moves, the shaft in the diff or the drive shaft?
what yoke moves a 1/4"?
 

·
Registered
Joined
·
24 Posts
Discussion Starter · #5 ·
Yes the axle pinion and front driveshaft. The actual pinion moves around which is making the yoke on the differential side of the front driveshaft loose too. Basically if I wiggle the driveshaft the whole driveshaft and pinion will move.
 

·
Registered
Joined
·
5,007 Posts
Rotational movement is fine. That is the backlash on your gears. In and out or up and down movement is not fine; meaning your pinion bearing preload is way out of whack, possibly damaging your bearing if its been driven on.
 

·
Registered
Joined
·
2,321 Posts
ay i could be wrong.......you got a mechanic you trust? that knows diff's. get an opinion and estimate.

but know, the D30 is only worth 150$. spending 600 to fix it, may not be the cheapest option. you could find a fresh part out, with the same gearing for way less.
if you go off-road it's the perfect excuse to find an HP D30 axle that matches your rear gears.
 
1 - 9 of 9 Posts
Top