De-Shimming the 2004 rear axle ?:)

minutofgroundhog · #1 (**permalink**) 07-04-2007, 11:42 PM

Ok so I put the ford lowering shackles on and now the driveshaft vibrates. (pinion angle ) So I am looking at it and see a pinion shim (factory) installed with the fat end forward. (making pinion angle worse ) Now for the stupid part. I can't seem to separate the spring from the spring perch. What is the secret of this great mystery ? Thank you and sorry for digging up an old post.
(I was googling before it got dark outside )

Silver Streak · #2 (**permalink**) 07-05-2007, 08:59 AM

When you put the lowering shackles on they should have made the pinion angle better, not worse. If the shims were installed to rotate the pinion up at factory height there is probably something wrong somewhere. Maybe the center section isn't on the axle tubes at the correct angle?

Edit: Forgot about your question. Sometimes the locator bolts that hold the springs together are in a bind in the holes on the axle. Usually a little work with a prybar will get them out.

minutofgroundhog · #3 (**permalink**) 07-05-2007, 12:12 PM

I had a feeling it was just stuck in there, thanks.With the stock shackle no vibe at all. With the long shackle, much vibe. So I opted for the second hole in the shackle, some vibe. As far as the shims go they are factory. They rotate the pinion down. If I accellerate hard, no vibe in either shackle position. So I thought if I removed the shims, the pinion would raise up, and maybe I could go to the last hole on the shackle.
I traded a f350 4wd in on my Lightning. It had an extreme pinion angle with no vibe (just ate U joints up real fast) Anyway thanks again I got to look for my air chisel.

Ford_Six · #4 (**permalink**) 07-05-2007, 12:39 PM

You need to pull the u-bolts first (should replace them any time they are loosened), then use two heavy duty C clamps to hold the springs together and pull the center bolt (if the shims are actually bolted to the leaf pack). Reassembly is the reverse- Just don't take the springs apart without clamping the pack.

minutofgroundhog · #5 (**permalink**) 07-05-2007, 02:00 PM

Roger that on the C clamps. If the center bolt continues to spin, shall I whiz wheel it off ? What is a good replacement bolt (Allen head ? ) Thanks for the reply.

Kyle

Silver Streak · #6 (**permalink**) 07-05-2007, 03:37 PM

Duh. When I posted my comment above I had just finished working on a truck with the axle above the springs. The Fords aren't like that. My bad.

Ford_Six · #7 (**permalink**) 07-06-2007, 12:07 AM

Only if that bolt is actually holding the shim on- separate the axle from the spring on one side to see if the shim comes loose. If not, then yeah, cut the bolt. I have taken a replacement bolt (1/2" or 9/16", don't remember now), and ground the head round to fit the perch when I've had to play with center bolts before. Make sure to use a grade 8, and use one that is a tight fit in both the spring and perch- nearly all the pushing force the truck receives goes through that right there. Any play, the hole gets hogged out, the truck dogtracks, and eventually the axle can move on the springs.

minutofgroundhog · #8 (**permalink**) 07-06-2007, 12:38 AM

Allrighty then, my Jardine cat back just came in from e-bay so hopefully this weekend I'll be able to do some work on the L. I made a goof buying chineese brake pads (ebay) don't do it I say ! I'll let ya know how all this turns out on Monday. Youse guys are da best !

minutofgroundhog · #9 (**permalink**) 07-11-2007, 01:07 AM

Hey I loosened the U bolts on both sides and re-torqued them evenly ( they seemed to be a lot of threads on the front side compared to the aft ) and my vibe has diminished to almost nothing. Also the Jardine sounds awesome, looks great, and was $ 230 shipped. As I was driving home from work tonight a Dodge Hemi thought he would try, but alas he could not.

K&N ; IAT resistor ; 170 thermostat ; Jardine catback ; that is all...