Hi everyone, my fiance has a 2000 Jeep Cherokee 4.0 V6 that is ticking very loudly. The faster you go, the faster the ticking is. However when she gets it up to around 50mph it quiets down. It is still there but not as bad. I pulled the valve cover off, and the rocker arms look good. I cranked the motor and I would think oil would be going all over the place. Its just a little bit covering everything. There is no loss of performance driving, just the annoying ticking. I have heard it could be flywheel or lifters. How can I determine which it is without dumping alot of cash into it? Thanks in advance!

 

It's a 4.0, and it will tick for hundreds of thousands of miles. If you have good oil pressure you will be fine. What brand oil filter is on the engine?

 

I am not sure, I will have to look when I get home. What kind should it have on there? And how can I quiet the ticking?

 

Wix or Mopar filters are the most highly recommended. Stay away from FRAM filters, they are the worst possible filters you could buy.

 

Will switching to that oil filter quiet the ticking?

 

Maybe not, but the engine will be better protected. FRAM uses cardboard end caps and less filter media than most any other filter on the market.

 

Those V6's always tick.

 

Especially when you line the cylinders up in a row.

 

So it sounds to me its a common thing maybe a design flaw. What is causing it to tick? Is there any way to quiet the ticking?

 

It's an engine that was designed in the 60's and tolerances were not what they are in today's modern engines, but they last forever if maintained.

 

Puts me in mind of the old Timex commercials, "Takes a licking, keeps on ticking!"

I've done a lot of research on the "4.0 tick" and nobody seems to actually know what's making the tick, but I guess it really doesn't matter, although my WJ seems quieter than my ZJ was.

From what I've found, the oil feed holes to the lifters are tiny and can easily become plugged or reduced in size by debris. Everything in the engine is lubricated with one main oil gallery, so as the engine bearings get worn, the lifters get less flow at idle. The tick is most often #1 and #6 because they are the farthest from the pump. They get oil, but not enough flow to close the valve lash at low speeds.

Any heavy ticking can also be a cracked piston, but unless you've heard one, it's difficult to tell. It's more of a localized sound, only once every revolution, and doesn't go away with speed.

 

Will seafoam help?