Knocking noise

[phishmun2001]

I have a 2000 jeep cherokee. I has about 95,0000 + miles on it. I can hear a knocking noise in the engine. The noise becomes less apparent when i let the car sit and warm up. I've tuned it up and given it an oil change. But still no change. Does anyone have a clue to what this may be? I'm afraid this might be it for my baby.

[1996Chreokee]

Could be piston slap.... is it real loud? or does it change when you gas it hard?

[phishmun2001]

Yes, if you press on the gas it gets really loud. However, if the car is warmed up for awhile, the noise is less apparent. If I don't let the Jeep warm up, it sounds like someone is hitting the car block with a crowbar.

[1996Chreokee]

Does the noise sound low like in the oil pan area (rod)...? or in the middle of the engine ( piston slap) or the top of the engine (lifter)?

Are there any metal shavings in the oil?

[phishmun2001]

I don't see any metal shavings in the oil. It does sound like it is comming more from the middle of the engine. Is piston slap serious? Curable? Like i said the noise is less apparent as the engine warms up. The less I let the engine warm up the louder it will be.