4.0 lifter noise solution ?

[Strokermjcomanche]

My friend has a 90 4.0 xj with 120 k miles on it and the lifters make quite a bit of a clacking noise at idle .His oil pressure is at roughly 25 lbs at idle and slowly climbs up to 40-45 at higher rpms ( 2500-3000) Just seeing what can be done in terms of oil , additives etc before replacement . Thanks in advance .

[shelbyluvv]

The only real fix is replacing them. He could try to run some Marvel Mystery Oil through it and see if that helps.

[Strokermjcomanche]

Thanks Bo . Even if the mystery oil prolongs replacing them till summer when it's not 10 degrees out its a plus . Thanks again .

[yxmj]

Here is somthing I first used on a really noisey YJ that worked great so now i do it on all of my jeeps.....it takes a bit of time depending on which way you go....might be worth a try.. :thumbsup:

 

Dr. YXMJ’s Oil Wash…

There are 2 ways 2 do this the quick way and the extreme (right) way…

1. Quick Way Go to your low budget auto supply store (Walmart??) and buy the cheapest motor oil and filter you can find. Also buy a high quality (I run 10W30 synthetic oil and filter)
2. Go home and check your oil…..I would assume it is down ½ -1 quart
3. Add (here is where different recipes come into play) your choice to top up….ATF….Sea-foam (my favorite)…..Diesel fuel….
4. Run the truck up to operating temp shut off and safely and carefully change the oil as usual.
5. Change to cheap filter and add cheap oil…….(here is where some more sea-form is nice).
6. Go for a drive or run the motor for 20 min.
7. Shut off and safely and carefully change the oil as usual.
8. Now add the good oil(10w30) with a new good filter……..Did that solve it?

 

1. Extreme Way Go to your low budget auto supply store (Wal-mart??) and buy 2 complete changes of the cheapest motor oil and  2 filters you can find.
2. Go home and check your oil…..I would assume it is down ½ -1 quart
3. Add (here is where different recipes come into play) your choice to top up….ATF….Sea-foam…..Diesel fuel….(I love the sea-foam)
4. Run the truck up to operating temp shut off and safely and carefully change the oil as usual.
5. Change to cheap filter and add cheap oil…….(here is where some more sea-form is nice).
6. Go for a drive or run the motor for 20 min.
7. Shut off and safely and carefully Drain the oil
8. Now drop the oil-pan and remove the valve cover….take both to your parts washer or a least a tub with some Varsole (you single guys can use the kitchen sink….the married ones know better) and clean both until you are willing to eat eggs out of them. (If you want now is a good time to add some fresh paint).
9. Replace both with new gaskets or high quality RTV silicon.
10. Change to your second cheap filter and top up with NEW cheap oil.
11. Drive down to the auto parts store and buy a high quality  (I run 10W30 synthetic) oil and filter. Listen to you motor….is it getting better??
12. At home drain out that new cheap oil and change the filter to the good one….fill up with the synthetic

I hope this Helps someone out there   :thumbsup:

[Dando]

Before replacing my engine in the fall I was having an issue with pretty low oil pressure, I tried changing over to a slightly heavier oil with acceptable success. 15w40 got me by for about a month while I prepared for the swap, not sure on the long term viability of this but I wasn't concerned with that myself, just trying to buy some extra time.

[Incommando]

Before replacing my engine in the fall I was having an issue with pretty low oil pressure, I tried changing over to a slightly heavier oil with acceptable success. 15w40 got me by for about a month while I prepared for the swap, not sure on the long term viability of this but I wasn't concerned with that myself, just trying to buy some extra time.

Try 20w50 as the weather warms. Things like Restore might buy you a little extra time. None of these will fix anything but it is possible to buy some time if you are lucky. As to 15w40 it is a weight that many of us run anyway.

 

There is plenty of anecdotal evidence that switching an older and/or high mileage engine over to synthetic can hasten an engine failure and lead to oil leaks. I can tell you from experience that a seemingly OK 2.7 V6 ( admittedly a junk engine design even if it did have 145,000 on it) blew up within 1,500 miles of changing it to full synthetic oil. Much like "which oil or filter is best" there are tons of opinions on this. I think it would be worth a few minutes of anyone's time to research this to make a more informed decision prior to making such a switch. Remember that the vast majority of our 250,000 mile plus 4.0's have never seen a drop of synthetic oil and are doing fine. Being vigilant about oil changes is probably more important then the oil you use in these engines, anyway.

[johnj92131]

 

Before replacing my engine in the fall I was having an issue with pretty low oil pressure, I tried changing over to a slightly heavier oil with acceptable success. 15w40 got me by for about a month while I prepared for the swap, not sure on the long term viability of this but I wasn't concerned with that myself, just trying to buy some extra time.

Being vigilant about oil changes is probably more important then the oil you use in these engines, anyway.

 

 

Exactly!  Changing oil gets rid of the garbage and contamination in the oil.

[metrictonner]

Low oil pressure?  Don't forget the HO oil pump fix.  I changed mine and now have pressure to spare with 10w30 oil winter and summer with no lifter clacking, piston slapping or bearing knocking.

[Incommando]

Low oil pressure?  Don't forget the HO oil pump fix.

Can you elaborate on this? Is it replacing the stock pump with a high volume version, a high pressure version, or something else? Thanks