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Pinion angle causing bottoming out?

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Old 02-24-2008, 05:45 PM
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Default Pinion angle causing bottoming out?

All,

Installed FT upper & lower control arms this weekend on my 2 door. Have already added JE Reel driveshafts. I have a 4" lift.

I aligned the pinion so it is a straight shot to the driveshaft. Looking at the springs, it seems like with it at this steep of an angle, it has the springs hitting the axel at a funny angle.

Took it to the "test" off-road area tonight. I bottomed out on the rear going over a couple of ruts. Hadn't done this before (although jeep is only a few months old and I haven't had it off road much).

I'm wondering if the steep angle may be causing this. Or maybe bottoming out is to be expected??

tnx

Blue Mesa
Old 02-24-2008, 06:15 PM
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Well, you don't usually go STRAIGHT in....and, depending upon what you mean by "bottoming out"..it might be normal anyway.

Do you mean the tires hit the inside of the wells, the shocks hit maximum compression, or the coils mashed down to full compression, or the bump stops hit in the rear?

All of those are some times called bottoming out.

The angle of the coil itself is unlikely in any case to be involved.

Its more likely to be some combination of that either your bump stops are too long, your shocks can't compress enough, your coils can't compress enough, the tires are too big, or you needed a BL to allow stuffage....etc.



What do you think?

Typically, you have a slight down angle for the drove shaft, and, typically, if you screw up the pinion angle (enough) you get vibes....if no vibes...probably ok to leave it.

As to the bottoming out...what happened?
Old 02-25-2008, 02:42 AM
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Good questions. Not sure, it was at night. I was going about 10 - 15 mph and drove across a washout rut in the road. Rear tire/wheel hit max of one of the items you listed. Pinion was at 10 degrees with axel at 20 degrees, so I put in the FT bars and adjusted pinion to 20 to be straight with driveshaft. Vibrations went away. Maybe I just hit it funny. Not sure what else to say. Guess I need to investigate off-road further.

BTW your Jeep photo in sig is awesome!

Blue Mesa



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