Lift complications...

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Oct 11, 2002
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Okay, so now that I've got the 4" Skyjacker lift, 33's, and assorted components installed on my '78 FJ40, I took "Tony" into a shop for an alignment check. After being checked by two different mechs during the past two days, I was told that they couldn't really do anything for it. From what I've been told, it is the usual good news/bad news scenario.

Good news: The rear axle looks beautiful.
Bad news: The front axle is cock-eyed. The axle is sitting 7/10ths of a degree out of square with the passenger's side being slightly forward of the driver's side, and it has a negative camber. The suggestion is to take it to an off-road shop & see if they can use axle shims to straighten things up.

For the axle being slightly cock-eyed to the frame, I think that I can loosen up all the U-bolts, and get the 7/10ths of a degree between the two sides. Granted, there isn't much movement with the leaf spring centering studs & spring perches, but 7/10ths of a degree isn't that much of an adjustment. The main problem is trying to figure out how to correct the negative camber.

So, the questions are:
Has anyone else ran into this problem?
If so, how was it corrected?
Are there any other suggestions?
 
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Woody

From his website it looks like he is using stock shackle forward with stock length anti-inversion shackles.

Camber is a knuckle problem, not a spring problem.


Is it Driving funny???
 
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fj40.1978.home.comcast.net
As, Slowerthanu noted, I am running the stock shackle-forward design with stock-length, anti-inversion shackles.

As for drive-ability, it actually rides better than what it did in its stock form, but from the shape of some of the old rubber bushings, it is little wonder.

To make this a little easier, I created a quick html page on my site with the values from the print-out I got from my shop.  You can find that page at: http://home.attbi.com/~fj40.1978/alignment.htm

And, as you'll notice, I screwed up when I said camber...it is actually the caster that's out-of-whack.
 

woody

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looks to me like you need to drop in a 4 degree shim and reset your caster to +1.5 degrees, a tad higher than factory +1, and better for driveability with larger/wider tires.
 
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heh...don't you have something better to do, woody!?  :D Not that I'm complaining, mind you!!

I now that the leaf spring centering studs on the new leaf packs are moved back an inch or so...which makes sense, in order to keep suspension geometry.  And the explanation from the shop was that I needed to rotate the axle...so that the nose cone on the diff/third member moves down some, but this seems contradictory to the most of what I've learned about lifts & pinion angles.

Listen to me, a computer geek questioning numbers...hehe  ;)
 

woody

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Halo3, that's exactly right. You want the pinion to point down slightly. As the suspension cycles, with your front shackles, it will rotate slightly up at extension. In short, your pinion is pointed too high in front now.

I got nuthing better to do....cept finish my own junk and get it on the trails!!
 

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