Lifter noise in 98 Jeep Grand Cherokee 4.0L

[bullitt9350]

Did some searching through the forum, thought I found an answer, but that didn't pan out as well as I had hoped.

Just bought a 98 Jeep Grand Cherokee with the 4.0L engine, 86K miles. Didn't have any piston slap/lifter noise when I bought it. I changed the oil a couple days after I bought it with Quaker State High Mileage 5w-30/Fram PH16 filter. Then I had lifter noise.

Searched around here yesterday, and then last night I changed it again with Chevron Delo 15w-40. Helped a bit, but I still hear it.

Any ideas on what I can add to help quiet the lifter noise? My 91 Cherokee with 200K does it and sounds like a diesel engine its so bad, I don't want this one going that route so soon.

Thanks in advance, sorry for the long post.

 

[etech]

This might be a solution.
jeepforum

 

[Bror Jace]

Also bullitt9350, if it is a sticking lifter caused by the build-up of crud in the lifter bores, you'll want to give the extra detergents in the gas/diesel oils more time to work.

--- Bror Jace

 

[Motorbike]

Try the Mobil Drive Clean Plus HM synthetic blend oil for a couple of intervals with an oil filter from NAPA .

Both vehicles IMO.

 

[bullitt9350]

Thanks for the replies. I'm getting ready to swap out the engine in the 91 for a 4.7L stroker I built so I'm not too concerned about it. The new engine will run synthetic as soon as the break in period is over.

 

[Jerry]

Auto-RX worked great on my son's Jeep, quieted down after a few hundred miles, fine through rinse and then Syntec 10W-40..