[Old Dogger]

2003 4.0 engine. I have owned the jeep for about 6 months. It has 49,000 miles on it. The engine is very clean inside when looking with a mirror and flashlight through the oil filler area in the valve cover. The oil only has about 500 miles on it since last oil change. Valvoline 10-30 weight with a Wix oil filter. I started it up today and moved it out of the garage. It sat for about 3 hours, then I put it back in the garage so far no lifter noise of which I have never had any lifter noise. I started it up this evening and had some lifter noise for about 5 seconds and then it went away. We did some Christmas shopping and the Jeep was restarted about 6 different times with no noise. So the bottom line is I only have had it this one time. The oil level is at the full mark and the engine does not seem to use any oil.
Has anybody else ever heard lifter noise at cold start up on your 4.0 engine?
Is this anything to be concerned about, or is this normal for the 4.0 on rare occassions?
I am going to add about a half pint of Marvel Mystery oil to it. Marvel has been used for over 60 years to help with lifter issues.

 

[UnlimitedRubicon]

Has anybody else ever heard lifter noise at cold start up on your 4.0 engine?

I have occasionally had some noise on cold start up but it seems to be a random occurrence.

Is this anything to be concerned about, or is this normal for the 4.0 on rare occassions?

I don't know if it's something to be concerned about but it's been normal for my 4.0 on rare occasions.

 

[Rubicondon53]

Normal,, I always wait till warmed up before I move it..

 

[JeepnJim]

All of my 4.0 engines have done this. Two Cherokees and my Wrangler. I rebuilt one of them once, a Cherokee, and it didn't do it afterwards. Not the reason for the rebuild but just an observation I made. Must be characteristic of them to some extent.

 

[Old Dogger]

I just bought my Jeep and it makes that lifter noise when cold for a few seconds. My jeep only has 27,000 miles on it.
I am also familiar with Marvel Mystery oil and am going to add some to my engine.
Marvel is 4.9 viscosity and is a very high detergent for cleaning internal engine componet's and is great for cleaning hydraulic lifters. It is also a excellent lubercant for air impact wrenches. I have also used it in heavy equipment diesel engines as a flush before oil changes.

 

[jeepwayoflife]

Totally normal :thumb: takes a while for the oil to reach the lifters

 

[Moabrubi]

I did, got bad enough that I took it to the dealer and it ended up the lifters were worn really bad. Got the Lifters, Cam, and OPDA replaced under warranty. Runs like a champ now, I actually had a noticeable increase in ponies after it was fixed. It's normal but isn't if that makes any sense.

Guess I should add that additives are just band-aids to quiet it down.

 

[Slider57]

Just bought my '00 TJ 4.0 last week & I was wondering what that noise was. Now it makes sense.
Yeah, that Marvel Mystery Oil is something. I used to sell the piss out of it when I worked for NAPA

 

[JeepnJim]

I didn't know it had piss in it. So that's the mystery!

 

[Rubicondon53]

Just bought my '00 TJ 4.0 last week & I was wondering what that noise was. Now it makes sense.
Yeah, that Marvel Mystery Oil is something. I used to sell the piss out of it when I worked for NAPA

Obviously you must not have lost any sleep over selling that stuff.. I don't recommend using additives in gasoline engines, unless the thing is nearly shot and runs like crap and you're either gonna dump it, or rebuild it soon.. Diesels are different animals.

 

[Old Dogger]

Thank all of you for your responses!
I don't normally believe in additives either, but have been using Marvel Mystery oil for over 50 years in engines and know from experience that it does help lifter issues. You only add 1/2 of a pint so the ratio to oil is very low.
What I am learning from all of you is that the 4.0 is a good reliable engine. I guess from what I am also hearing is that a little lifter noise on rare occassions is normal. I suppose that the one time that it happened, for what ever reason the oil bleed down from the filter and hopefully won't happen again.
Have a great Turkey day!!!