Random Engine Clunk

[a.jeeper]

Hello,
1999 Jeep Cherokee
4.0
Auto
So it's got a wierd clunk when in park or neutral, and when stopped in Drive. No rhythm. Sounds like it's coming from the oil pan. Doesn't change with engine temp.
I've dealt with flex-plates. This is different.
Linked is also a video of what it sounds like. As you can tell I still removed the flexplate just to check.
I'm clueless at this point.
https://youtu.be/gKxw1Zzkuhs
Thank you!

 

[old_man]

If you put it in drive, hold the brake, and apply a bit of gas, does it change?

When you say you removed the flex plate, do you mean you removed the inspection cover? Removing the flex plate entails dropping the transmission.

 

[RCP Phx]

That's a weird kind of sound. Get a piece of pipe so you can listen in different areas!

 

[a.jeeper]

My apologies, yes the inspection cover not the whole flex plate. And I haven't got a chance to try pressing gas while holding brake or using a pipe. Because today when I came home and it was all warmed up, I laid under it for some time and not a single clunk. So there's something new, guess it does change with temp.

 

[Saudade]

Do you not hear it when driving? What about coasting in neutral?

Just for grins, make sure you don't have an exh leak.

 

[Jeff in VA]

Loose starter bolts???

 

[a.jeeper]

I'll check the starter bolts. But it doesn't change in neutral. However when in drive it is silenced, so that goes without saying that, putting in drive and gassing makes it quite.

 

[RCP Phx]

What about it in drive but with the transfer case in neutral?

 

[trippled]

Check the torque converter bolts. It's very possible the flex plate is cracked too. And highly unlikely you will be able to see the cracks without completely removing the flex plate.

 

[a.jeeper]

Starter bolts are good. Exhaust, everything from the exhaust manifold is new. Torque converter bolts were tightened with loctite a few months ago, I can still double check though. From listening underneath, I'm focused on the engine. Really sounds like the back end of the oil pan. My question for myself right now is, what in the engine could possibly be making a noise like this?!