Rotella Jeep 4.0 1994
- Thread starter dgee
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I ran 10w30 M1 & Pureone (6-7.5 K OCI) in my 95 JGC 4.0 for 167,000 miles without issues. Sold it to a relative out of state and it is still going strong. Only problem was a replaced rear engine seal. 5w40 is good but, I wouldn't use heaver unless absolutly needed due to consumption issiues
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Despite the high power to displacement ratio (at the time the engine was developed) the 4.0 is a low tech engine. I would consider running 15w-40 summer and the 5w-40 winter. the advantage of either of those oil is that they dont fall into the "low zinc" category. and 5w-40 is basically a robust Euro spec for German cars - well-suited for long oci's. if you want to run a larger filter, run the equivilant of a motorcraft FL1A (Fram PH8) on your rigs. i've had 2 of the 4.0's and loved them!
Originally Posted By: tomcat27
Despite the high power to displacement ratio (at the time the engine was developed) the 4.0 is a low tech engine. I would consider running 15w-40 summer and the 5w-40 winter. the advantage of either of those oil is that they dont fall into the "low zinc" category. and 5w-40 is basically a robust Euro spec for German cars - well-suited for long oci's. if you want to run a larger filter, run the equivilant of a motorcraft FL1A (Fram PH8) on your rigs. i've had 2 of the 4.0's and loved them!
how long of an oci would i be able to run with the T6 vs. 15W-40
Despite the high power to displacement ratio (at the time the engine was developed) the 4.0 is a low tech engine. I would consider running 15w-40 summer and the 5w-40 winter. the advantage of either of those oil is that they dont fall into the "low zinc" category. and 5w-40 is basically a robust Euro spec for German cars - well-suited for long oci's. if you want to run a larger filter, run the equivilant of a motorcraft FL1A (Fram PH8) on your rigs. i've had 2 of the 4.0's and loved them!
how long of an oci would i be able to run with the T6 vs. 15W-40
In warm weather, you can run the 15w40 no problems. As it gets colder, the 5w40 will work OK.
I used to run the 5w40 Rotella year around in my '88 Cherokee with the 4.0. I stopped when: I grew tired of keeping a special stock of oil for just the Jeep (tried Rotella in my F150 and stopped after a year when my fuel mileage was substantially lower - over 5%, but never noticed the same effect in the Jeep), and the oil pressure was high in the dead of winter, and stayed that way for a very long time. Basically the guage would end up just over 60 psi, and stay there in cold weather. Regular function is 60 psi at startup cold, then dropping a bit to 50-55 psi (depending on the weight) at power, 25 psi at idle. Its been that way since new.
5w40 worked fine and UOA's showed wear was about the same between a year around 5w40 regimen versus the 5w30 winter/10w30 summer that I have returned to.
I used to run the 5w40 Rotella year around in my '88 Cherokee with the 4.0. I stopped when: I grew tired of keeping a special stock of oil for just the Jeep (tried Rotella in my F150 and stopped after a year when my fuel mileage was substantially lower - over 5%, but never noticed the same effect in the Jeep), and the oil pressure was high in the dead of winter, and stayed that way for a very long time. Basically the guage would end up just over 60 psi, and stay there in cold weather. Regular function is 60 psi at startup cold, then dropping a bit to 50-55 psi (depending on the weight) at power, 25 psi at idle. Its been that way since new.
5w40 worked fine and UOA's showed wear was about the same between a year around 5w40 regimen versus the 5w30 winter/10w30 summer that I have returned to.
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Originally Posted By: dgee
how long of an oci would i be able to run with the T6 vs. 15W-40
What type of mileage will it see? You should be good for 6 months to start off with, imo. If it's low enough or high enough, one year could work too.
how long of an oci would i be able to run with the T6 vs. 15W-40
What type of mileage will it see? You should be good for 6 months to start off with, imo. If it's low enough or high enough, one year could work too.
Originally Posted By: Gary Allan
Originally Posted By: dgee
how long of an oci would i be able to run with the T6 vs. 15W-40
What type of mileage will it see? You should be good for 6 months to start off with, imo. If it's low enough or high enough, one year could work too.
about 14k a year. ALL highway
Originally Posted By: dgee
how long of an oci would i be able to run with the T6 vs. 15W-40
What type of mileage will it see? You should be good for 6 months to start off with, imo. If it's low enough or high enough, one year could work too.
about 14k a year. ALL highway
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You should be able to make RTS work for a year.
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