'02 Jeep TJ 4.0 under valve cover pics

[AZjeff]

New to me, oil history unknown. 115k miles on the Jeep. It's done 8k miles in the last 8 years. Fresh oil change unknown oil and a Wix filter. Pretty clean in there. More about the Jeep later.

 

[Furious]

Looks fairly clean, The 4.0 is very reliable. The one thing you need to be careful with is the cooling system because 0331 heads are prone to cracking especially if overheated. And 2002 is one of the years that may or may not be a 0331.

 

[Nick1994]

Nice Jeep!

Cooling system maintenance is 100% key on these.

 

[Chris142]

Looks fairly clean, The 4.0 is very reliable. The one thing you need to be careful with is the cooling system because 0331 heads are prone to cracking especially if overheated. And 2002 is one of the years that may or may not be a 0331.

02 will have the upgraded tupy head.

 

[Chris142]

That's about what mine looked like @150 when I replaced my valve cover gasket . I'd lose those original cooling hoses asap.

 

[Allaneddie]

New to me, oil history unknown. 115k miles on the Jeep. It's done 8k miles in the last 8 years. Fresh oil change unknown oil and a Wix filter. Pretty clean in there. More about the Jeep later.
View attachment 145105View attachment 145106View attachment 145107

that 4.0 I6 is a nearly indesctructible engine. That one is just broken in. Run it.

 

[Furious]

02 will have the upgraded tupy head.

Not all of them.

 

[Kruse]

that 4.0 I6 is a nearly indesctructible engine. That one is just broken in. Run it.

EXCEPT when they throw a rod through the side of the lock for no reason at all. EXCEPT when it has the 031 head on it.
Don’t ask me how I know..after owning 3 Cherokees and a Grand Cherokee, all with the late 90s 4.0 engine.

 

[Chris142]

Not all of them.

Mines an early build. Late 01 and has the tupy head

 

[addyguy]

Looks great, very clean. I was going to say ‘hope Chris142 sees this’!
Worked with a guy years ago that had a Jeep like this, beat the life out of it hard core off-roading a lot.
Has to replace a lot of parts, but the 4.0 was rock-solid!

 

[bullwinkle]

Looks good! My old '98 XJ 4.0 was still clanking along at 230K when the dreaded rust monster got it too bad. Son tried to kill it a couple times, but couldn't do it. Now it lives down by the river as one of my brother's friend's farm truck.

 

[AZjeff]

Built 4/02.

 

[KCJeep]

Looking good!

 

[Donald]

Looks fairly clean, The 4.0 is very reliable. The one thing you need to be careful with is the cooling system because 0331 heads are prone to cracking especially if overheated. And 2002 is one of the years that may or may not be a 0331.

There is also piston skirt cracking at least in 2001 4.0 engines. Maybe 2002:engines also.

 

[sw99]

Good looking 4.0L!