How tough is the 4.0l
Senior Member
Joined: Oct 2012
Posts: 797
Likes: 1
From: Jacksonville, FL
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0L
CF Veteran
Joined: Feb 2010
Posts: 1,152
Likes: 1
From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
bought it with a burnt valve, replaced the head. drove it but it would always just puke out oil from everywhere possible (rms, o rings, valve cover, PCV valve, etc) i could never figure out why. then one day i heard a loud knocking sound coming from the engine. i thought it was a rod bearing or something. took the engine out and pulled the head and found the hole you see there. this was at 207k miles. the PO had put on some "Junkyard injectors" as an upgrade. i think they were clogged, running lean or something because that would explain the burnt valve and a hole in the piston. i have since put in rebuild Bosch type 3s, and advise against junkyard injectors. i also think that the piston may have started out with a crack and was allowing combustion pressure to get past the piston and into the crankcase, pressurizing everything and forcing the oil out.
CF Veteran
Joined: Feb 2012
Posts: 1,249
Likes: 12
From: Hamburg AR
Year: 1995
Model: Cherokee
Engine: 4.0 HO
Senior Member
Joined: Jul 2012
Posts: 860
Likes: 0
From: middleburg fl
Year: 1998
Model: Cherokee
Engine: 4.0
I won a open class competition mud bog in my cherokee with bald 31's with no oil and sea water in the rad. Then I flipped it 4 times drunk trying to shoot heroine on the freeway driving home. Still runs fine today, just put a lil lucas in the motor.
My original A/C works perfect too..
My original A/C works perfect too..
Seasoned Member
Joined: Jan 2011
Posts: 493
Likes: 0
From: Grand Haven, Michigan
Year: 1999
Model: Cherokee
Engine: 4.0 I6
my question is:
why dont they use iron blocks and heads in modern newer vehicles (maybe they do, i dont know)
is it b/c of emmisions?
obviously they last, they can go thru h*** and back and still live
why dont they use them today?
why dont they use iron blocks and heads in modern newer vehicles (maybe they do, i dont know)
is it b/c of emmisions?
obviously they last, they can go thru h*** and back and still live
why dont they use them today?
CF Veteran
Joined: Feb 2010
Posts: 1,152
Likes: 1
From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
CF Veteran
Joined: Jul 2009
Posts: 2,522
Likes: 0
From: New Jersey
Year: 2000
Model: Cherokee
Engine: l6 HO
Weight and it's just the way they do It nowadays. Which is a shame because you overheat an aluminum motor your in trouble. It's crazy I can drive my jeep then let it sit for an hour in the cold and it's still warm when I fire it up. My girlfriends rav 4 gets to temperature in about 10 seconds.
It must be more cost effective. Less weight, easier to manufacture... It sure would be nice if they were able to bring back the l6 but sadly that will never happen
It must be more cost effective. Less weight, easier to manufacture... It sure would be nice if they were able to bring back the l6 but sadly that will never happen
CF Veteran
Joined: Feb 2010
Posts: 1,152
Likes: 1
From: La Habra, CA
Year: 1988
Engine: 4.0 RENIX
