I had to remove the two rear ,and passenger front, wheels off my 2008 2dr this morning and noticed that the front wheel mount (not sure exactly what you call it) has what looks like some sort of retaining clip/washer on the bolts. It looks like a washer with slots that allow it to act like a retaining clip to the threads of the bolts, one per bolt. The two back don't have these clips. I haven't checked the front drivers side yet but will tomorrow when I remove it.

I thought I read somewhere that these are supposed to be removed if aftermarket wheels are installed, ION Alloy 171 in my case, but I cannot find the source again. If I recall correctly it had something to do with being a source of vibration or something of that sort when the clips are left in place and aftermarket wheels are installed. I've been chasing down a vibration in my front end and since I noticed the clips this morning I got to thinking...

What is the purpose of the clips?
Can I remove them?
Should I remove them?

 

The clips hold the rotors on as the Jeep proceeds down the assembly line.

You should remove them when installing aftermarket wheels. The new wheels may not have clearance for them.

Leaving them on may cause the wheel to become loose.

Here is a picture of one thing that can happen.
Notice the elongated holes in the drum/rotor, due to insufficient clamping force.
The symptom in this case was a clunk when the brakes were applied.

 

^^^ What the smart man with picture said.