I'm afraid to ask what this is

OK so I have a 2000 XJ 4.0 about 235,000 miles on it. It's started clicking real bad in the front near the timing cover and was taking longer to start than usual so I figured probably the timing chain. So I parked it. Pop open the timing chain cover to put the new chain on and notice the timing chain is not loose enough to be slapping the cover or anything else. So I look in the bottom and see this little broken piece of metal along with the rubber chain guide. What the heck does this broken piece go to? It's slightly curved with a groove on one side. [/URL][/IMG]
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Piston skirt.

Sorry for the bad news.

Need better pictures, but it doesn't look like a piston skirt to me.

It looks like aluminum. Please confirm.

Take pix from more angles.

Did you take a good look at the back of the timing chain cover?

Pull the distributor and check out the housing.

There aren't that many aluminum things in the bottom end.

If that is piston, that break would be all the way up in the ring lands. There would be more pieces in the oil pan.

You would have a break such as this -


What is throwing me off from being piston is the raised section below the groove (right where your thumb is holding it). I don't remember 4.0 pistons being designed like that. That seems more like distributor housing. Hard to judge the amount of curve though.

It's definitely the skirt.
See the hole for the oil drainage for the oil control ring?
the black section that looks raised is the teflon coating
His pictures are very close-up.

Yup! Agree w/ the piston skirt. Have a similar piece laying in a pan in the garage! Time to pull that puppy...