15w40?
#1
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Year: 2000
Model: Cherokee
Engine: 4.0 I 6
15w40?
I've seen many posts on here about people running 15w40 in their 4.0's I was just curious about how this works out .. I own a 2000 with 205000 miles and im wondering if the thicker oil would be good for the old motor or not .. Any advice would be appreciated
#2
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Year: 1988
Model: Cherokee
Engine: 4.0
I've tried lots of different types of oil, and have yet to be convinced that there is any noticeable difference between 10w30, 10w40, or 15wXX in a car or small truck. If it is cold, go for lighter weight. If it is hot, consider heavier.
Just don't use a fram oil filter ><
Just don't use a fram oil filter ><
#3
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Year: '96 and '97
Model: Cherokee
Engine: 4.0
I ran a lot of rotella t through my old 97 4.0.
I also ran it in my CBR and my klr650.
It made things simple. And cheap.
I also ran it in my CBR and my klr650.
It made things simple. And cheap.
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#9
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
10 degrees is a rare occurrence where i live, maybe once or twice a year. My engine is tired with 4 psi oil pressure with 15-40. It has had low pressure since I bought it 4 years and many miles ago. I bought a spare engine and decided "what-the-heck I am going to run 15-40 Walmart oil in it till it blows. Well it still runs like new (except 4 psi) and I am still waiting......
#11
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Year: 1999
Model: Cherokee
Engine: 4.0
10 degrees is a rare occurrence where i live, maybe once or twice a year. My engine is tired with 4 psi oil pressure with 15-40. It has had low pressure since I bought it 4 years and many miles ago. I bought a spare engine and decided "what-the-heck I am going to run 15-40 Walmart oil in it till it blows. Well it still runs like new (except 4 psi) and I am still waiting......
Don when I bought mine it had 220,000 on it and sounded a little loose on the top end for sure and made the same decision as you did. Have almost all the new parts and a fresh block in the shop waiting and waiting..............The damn thing just keeps running on now after 3+ yrs and I wondered if it would make it a month till it blew.
I run Rotella in it also a 5w40 and NAPA Gold filters. My DD's the 04 GC with a 4.7HO and the 13 Lincoln Town Car, 09 E-250 High Top Conversion Van all get Castrol 5W40 full Syn and NAPA Gold or Wix filters.
The only high mileage car I have ever ran full syn oil in is my 2004 GC "Overland" with the 4.7HO motor it has 208k and does not use a drop of oil between changes 6mo/6,000mi. It was an one owner car with all service records done on it at a Jeep dealership from day one. It was spotless inside/out.
#12
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
Don when I bought mine it had 220,000 on it and sounded a little loose on the top end for sure and made the same decision as you did. Have almost all the new parts and a fresh block in the shop waiting and waiting..............The damn thing just keeps running on now after 3+ yrs and I wondered if it would make it a month till it blew.
#13
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Year: 2000
Model: Cherokee
Engine: 4.0
15W-40 is designed for diesel engines. It does not provide good cold start protection in a gasoline engine. So, if you use it, will your engine blow parts through the hood? No. It's just less than optimal.
5W-40 is a no-brainer solution. It will give you excellent cold weather start protection. It will give you excellent operating temperature protection in warm or very hot weather.
Last week, Walmart had Shell Rotella 5W-40 T6 (that's full synthetic) on sale with a $5.00 rebate. You might check to see if that offer is still available. It's outstanding oil with plenty of zinc for the flat tappet cam. Be aware the Rotella T6 comes in 4-quart jugs. I bought two jugs and used most of it with a Motorcraft FL1-A filter which gives an extra 1/2 quart of oil capacity.
5W-40 is a no-brainer solution. It will give you excellent cold weather start protection. It will give you excellent operating temperature protection in warm or very hot weather.
Last week, Walmart had Shell Rotella 5W-40 T6 (that's full synthetic) on sale with a $5.00 rebate. You might check to see if that offer is still available. It's outstanding oil with plenty of zinc for the flat tappet cam. Be aware the Rotella T6 comes in 4-quart jugs. I bought two jugs and used most of it with a Motorcraft FL1-A filter which gives an extra 1/2 quart of oil capacity.
#14
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Year: 2004
Model: Grand Cherokee
Engine: 2000 4.0
So what is the difference between a gas and a diesel engine? If anything a diesel with its high compression is even more critical. It is the residual oil film on bearing surfaces that protects an engine on cold start ups. That film is still there with 15-40, probably more so.
#15
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Year: '96 and '97
Model: Cherokee
Engine: 4.0
I always used to catch the rotella t6 rebate offers. They run them quite often, and it's a great way to snag some super cheap, high quality oil. I had like 10 gallons at one point.