4.0 ticking noise


TJ Enthusiast
Jan 18, 2023
Hi all,
So my Jeep recently started making this ticking noise that to me sounds like a dropped lifter. My reasoning is because it goes away once I’m in high rpm, it’s only in lower rpm that it starts ticking again. It also sounds like it’s more towards the back of the motor and on the passenger side. Any ideas?
Lots of good videos on refreshing 4.0s on the Just Dex It YouTube channel.

I'd start with pulling the valve cover and check the rockers. Make sure they're all torqued properly and there isn't a smoking gun...huge amount of lash, completely loose... something like that.

I'd pull the oil pan and check for pieces of piston skirt. It's not a common failure, but I've heard/seen a few.
I read an article about bad piston runs on the 99 to 02 4.0 liter. I don’t remember the reason but it was usually the # 3 or # 5 that would get a crack. The guys that had the problem pulled the oil pan and manually brought the motor down to inspect each piston for cracking or chipping as well as inspecting the pan for chunks. Hopefully this is not your issue.