Most commonly it is a cracked exhaust manifold, just above the flange where it connects to the tail pipe. They all (original) crack. It's a Jeep thing as they say. I'm surprised yours got 204K without a crack. The crack is easier to see from underneath the vehicle.

-Bruce

 

absolutley.... every 4.0 i have owned (except my wifes tj) has had valve train noise.....drive on!!

 

lifter tick on almost every 4.0 I've seen.

 

My 4.0 with 219k ticks real bad, It sounds like a 6.5 chevy diesel when I start it cold. I've narrowed it down to piston wrist pins. I run 20w50 motor oil in mine and the V8 size can of that engine restore. That quiets it down a lot, im gonna run it this way until it just blows up then just put a new engine in it.

 

I am going with valve lifter. I had the same problem with mine last year. Found that the lifter was sticking. Identified the lifter, pulled the rocker arm and pushrod, and sprayed the top of the lifter with WD-40. I used a long, clean, steel rod to push on the lifter to work in the oil. Be carefull not to drop the rod or pushrod in the engine. Put it all back together and enjoy the peace and quiet.

 

i just tore down my 96 two weeks ago due to a loud tick...thought it was a bent valve but there was nothing wrong with them...i reseated them and bought all new lifters...they were like $2 apiece and then i put the head back on....fired it up and let it idle for about 30 minutes while the lifters built up pressure and it stopped ticking alltogether... total cost of everything with new pushrods was about $250

 

Im also going with valve noise. 360,000 and still ticking and still smoke the 33's.

 

Congrats on 360,000 miles.

 

Huh? it's a 4.0, they run forever

 

I highly doubt its the exhaust; I replaced the exhaust manifold less than a 2 months ago due to the crack in the collector. I sealed everything up with a gasket sealer and tightened everything down. I would completely rule out a exhaust leak, but like I said, I HIGHLY doubt its that.

 

Sounds like lifter ticks to me. My old XJ did it and had 275,000 miles and still ran fine. I wouldn't worry about it.

 

I bet lifter or valve. My dads 90 does it and has done that since as long as I can remember. My 94 only does it when I am more than .5 quart low on oil.

 

No way.


Notorious Jeep valve tap. Everyone gets it sooner or later. Got mine at 210k on one and 130k on the other. Valve/lifters.

Do the hot oil flush, stopped it on one, quieted it on the other.

 

You highly doubt it, but even new puppies die, and exhaust gaskets burn out.

 

Very true. And its just as sad when as when a new puppy dies.