XJ knocking/ticking?

TapouT

Well-Known Member
Joined
Oct 5, 2008
Location
Hickory nc
I have a '98 Jeep Cherokee with the 4.0 and it has a knocking/ticking sound. It has 164,XXX miles on it. It knocks when it's cold outside until the motor starts warming up but then it starts ticking? If I rev the motor up to about 2500 it will tick revving up and then it will sound like something's clanking around when the motor's revving itself down. Holds good oil pressure. Oil pressure is 40+ lbs on cold start and after the motor is very warm it stays around 25-30. Just changed the oil about 2 weeks ago with 10-30 high mileage and added some lifter quiet to it but that didn't help. Should I run a thicker oil and just not worry about it or is this a problem I should look into? I know the 4.0's last forever but this kinda scares me.
 
My wife's does the same thing. More in hot weather, I think it's a lifted collasped & the valve not opening correctly
 
had the same problem on my wifes TJ the #5 cyl int lifter was shot. The reason i asked about the trans,we had one here one time that had a cracked flywheel that mimicked an eng knock. We did not find it untill went to pull the eng for replacement.
 
I poured in a quart of lucas & it stopped for a while. Then it started & I changed the oil 15-40 rotella. Came back once so far.

How bad was it to change out the lifters?
 
It's an auto trans...is it safe to drive it like this? meaning is it going to hurt the motor or is it hurting it now with me driving it? i'm very easy on the Jeep because of the noise. should i maybe try running some lucas in it? thanks for all the help guys i appreciate it a lot! :beer:
 
took me a day in the garage with no air tools. helpful hints 1) pull intake and exhaust and head as 1 piece. 2) get a lifter removal tool, trying to fish them out with a magnet will drive you insane. 3) make sure you remove the clip that is under the intake that holds the fuel line. Don't ask how i know this ( " Honey maybe it's not coming out beacuse of that thingey under the silver thing is still hooked on " ) otherwise it's a breeze to do.
 
just did an entire upper on an 02 4.0 with a blown head gasket, he had a few lifters that had seized up and dished

i didn't have any problems fishing the lifters out with my magnet but i put a squirt of ATF4 down the lifter valleys on each one and let it sit a bit, then pulled them up and down as much as the lifter would wiggle until they were good and lubricated and then pushed them back down, got a good hold on them and up-see-daisy

the lifters on #6 are naturally the hardest ones without crawling all up in the engine bay

rockauto and a few other places carry victor reinz head gaskets for the 4.0's - they're pretty dang dependable gaskets

take the time to clean the carbon buildup out of the intake and head the best you can while you're at it, unless money is real tight, replace the valve seals, and measure your valve springs to make sure you're not running some fragged springs too while you're at it, can roll the push rods across a piece of glass to make sure they're straight although as cheap (relatively) as they are I usually replace them when i replace lifters
 
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