phillyxj570

when i start my jeep the engine makes a ticking noise while idling...as soon as i give it gas the ticking goes away...but if i come to a stop sign or red light the ticking comes back...until the engine warms up it sounds like it is coming from the front of the engine but i can not pin point it...any help or ideas is appreciated.

CHEVY SHOCKW4VE

mines doing the same thing. i popped the hood and it sounds like its comin from the valve cover. idk if i have a lifter sticking or somehting at idle. hopefully someone can help

84zmyfavorite

This is becoming more and more common, especially in the latter year 4.0s, I think because of the reduced levels of zinc/phospherous in 2004 year and later, "Energy Conserving"(5w-20, 0w-30, 5w-30, 10w-30) API SM rated motor oils. The later year 4.0s would most likely have been run on these newer oils most of their life vs. older engines that did get the better protection for flat tappet/camshaft engines like our beloved 4.0s. And 2.5s. But any year 4.0, from 87 to 06 can develop this problem, if driven aggresively on these lower level zinc/phospherous oils. The lower levels of ZDDP dosent offer the High shear protection needed in the camshaft lobe/ lifter contact area and wear occurs, with either the lobe rounding off, or the lifter wearing concave, or both, creating a gap between two when they should always be touching. That gap being made up as the camshaft lobe, when the lobe comes back into contact as the lifter is being rotated towards the lifter is what makes the "Tick, Tick".

CHEVY SHOCKW4VE

is their anyway to fix this ones it does it? or should you just rip the top end apart and replace it

CodeXJ

Most people just let them tick. Usually the tick is due to collapsed lifters that aren't fully pumping up, resulting in some play in between the rockers and the pushrods. It's common in higher mileage engines, not just Jeeps in general. The fix is usually to put in new lifters or run a thicker oil. For example, mine sounds like a coffee can full of marbles on 10w30 but is quieter with 10w40. It could, however, also be other things like damaged valves. Usually, if the engine is running fine, people just run thicker oil and keep driving.

djb383

What in-line engine isn't noisy???? It's a characteristic nature of the beast. The lifters and cam are on the side of the block (noise is easily transmitted) vs being buried deep inside the block as with a V type block. Ticking/clicking is normal for most in-line engines. The Jeep 4.0L only has 55 lbs closed spring pressure.....no extra ZDDP required there.

CHEVY SHOCKW4VE

never thought of it that way. my xj is my first car so im used to inline 6's