what oil are you using in your Jeep 4.0L
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I would be inclined to think that if it says 30F it is a misprint.
Sometimes they do put the wrong info in there. My 99 AX15 needs a GL-3 fluid according to the 99 FSM. The manual states GL-5. A no-no in an AX15.
..but ...the oil recommendation has been in all manuals for the 4 banger and the 4.0 from (AFAIK) 97-2002 (the 2.5 4 banger was discontinued at that time). It's the same in my 99 and 02 owners manuals.
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And actually, my 4.0 Grand Cherokee was very economical as long as it was cruising at 60 mph at 14,000 ft above sea level. No wind resistance.
Cruising, if you can get enough miles per warm up, the XJ's and the ZJ's don't do too bad. Long mileage works well for them. In a Wrangler, you would be very fortunate to break 20-21 on a long (tank full) run. 18-19 is average for my wife on her 25 miles one way commute. If she had an automatic, it be in V8 range in a chassis that weighs a ton more (something like a 2wd pickup with an SBC - that is, unless you believe what 2wd SBC pickup owners claim to get for mpg
). The Wrangler weighs just a tad more than an XJ (they're within about 200lbs of each other) ..but that frontal area trumps everything.
I imagine that Johnny's Unlimited is a gas guzzler that looks like it should be a fuel squeezer. I think some Hummers do better.
I would be inclined to think that if it says 30F it is a misprint.
Sometimes they do put the wrong info in there. My 99 AX15 needs a GL-3 fluid according to the 99 FSM. The manual states GL-5. A no-no in an AX15.
..but ...the oil recommendation has been in all manuals for the 4 banger and the 4.0 from (AFAIK) 97-2002 (the 2.5 4 banger was discontinued at that time). It's the same in my 99 and 02 owners manuals.
Quote:
And actually, my 4.0 Grand Cherokee was very economical as long as it was cruising at 60 mph at 14,000 ft above sea level. No wind resistance.
Cruising, if you can get enough miles per warm up, the XJ's and the ZJ's don't do too bad. Long mileage works well for them. In a Wrangler, you would be very fortunate to break 20-21 on a long (tank full) run. 18-19 is average for my wife on her 25 miles one way commute. If she had an automatic, it be in V8 range in a chassis that weighs a ton more (something like a 2wd pickup with an SBC - that is, unless you believe what 2wd SBC pickup owners claim to get for mpg
I imagine that Johnny's Unlimited is a gas guzzler that looks like it should be a fuel squeezer. I think some Hummers do better.
My last oci was a 0w30 Agrol PAO SL. Works ok but it does tick a little for about a minute when cold. Doesn't seem to make any other difference in quick cold starts or anything.
Will use a 5w40 or a 10w40 semi synth the next oci. I do 10 000 km oci which is about 9 months for that car.
Will use a 5w40 or a 10w40 semi synth the next oci. I do 10 000 km oci which is about 9 months for that car.
If you read all the posts you'll gather that almost any oil will do.Just regular changes are the key.
01 XJ: Royal Purple 5w-30
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Originally Posted By: 02zx9r
i dont have a jeep 4.0L
You are not alone. Don't feel so bad. Many have not enjoyed the raw power ..the, neck snapping, push you back in your seat acceleration ..and the outstanding fuel economy of this fine engine.
Someday, maybe ...but for now, you'll just have to live with envy.
i dont have a jeep 4.0L
You are not alone. Don't feel so bad. Many have not enjoyed the raw power ..the, neck snapping, push you back in your seat acceleration ..and the outstanding fuel economy of this fine engine.
Someday, maybe ...but for now, you'll just have to live with envy.
I've been using 3-in-1 Oil and am closing in on 400K miles.
Not quite, but I'm confident regular oil changes and anything close to normal oil will get me/us to 200K. 117K now on mostly dino 10W-30...
Not quite, but I'm confident regular oil changes and anything close to normal oil will get me/us to 200K. 117K now on mostly dino 10W-30...
The 4.0L is one bullet proof engine! I too get the lifter ticking, especially in cold weather. My Jeep has always had 10w-30 since it was new (dino always).. I am afraid that switching to a synt oil will make my rear main leak even worse. Should I still try a 5w-40??
Amsoil 10w-30 90% of the time with a couple of years of TSO in the beginning. All with annual OCIs.
I don't get the ticking at startup, now have 125k miles.
These are not quiet engines by any stretch though. Inline 6 OHV US engines are generally bulletproof but noisy.
I don't get the ticking at startup, now have 125k miles.
These are not quiet engines by any stretch though. Inline 6 OHV US engines are generally bulletproof but noisy.
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Mine made lots of noise at 240000 miles. 1/2 qt of PP 0w-20 syn actually made it quieter several times regardless of what else was in the sump. I believe I had stuck rings. After lots of seafoam, HDEO, HM oil, the noise lessened, but the PP trick always helped.
M
M
Sold my 95 GC 4.0 at 197,000 miles runing Mobil 1 10w30 and OEM and PureOne oil filters every 6-7,000 miles OCI. Sold running great without any oil problems except I had to replace the rea main seal 2X times. Today, probably would run Mobil 1 5w40 as it was not avail before I sold the Jeep.
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Chronic lifter noises are typically due to varnished oil passages. They restrict the flow to the top end of this engine. It really isn't anywhere near like you would see on a SBC. The oil kinda bleeds from the pushrods. This is about the only complaint (outside of a weeping/seeping rear main) that anyone has about this engine.
I'm running SSO...no noises other than the injectors and idle is smooth as silk.
I just picked up another Jeep this week, (this makes #7!) and I'm planning on using Schaeffer's 10w30 Supreme 7000, with maybe a little dab of Moly EP just to keep the lifter faces happy. Then again maybe not. Supreme 7000 is an excellent oil in and of itself.
My last 4.0L got Amsoil, and it liked it better than the Mobil 1 that I was using previously.
Like many have said, these engines aren't too picky about oil...Just run a good filter and stick to your oil change intervals and you'll be good.
My last 4.0L got Amsoil, and it liked it better than the Mobil 1 that I was using previously.
Like many have said, these engines aren't too picky about oil...Just run a good filter and stick to your oil change intervals and you'll be good.
I
I had two GC in the past with the 4.0 engines,out of all the oil i used the best was maxlife 10w30
i have a 94 ZJ 4.0 and it has 5w-20 pp in it. it runs alot better than it did with pp 5w-30. has more pep and less noise!
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