I have a "hard headed" relative with a 2006 Jeep I-6 4.0L Rubicon who recently had the engine rebuilt at 96,000 miles (he's the 2nd owner) . Moving on , he is very lax about oil change intervals so I put him into a Fram Ultra oil filter with Valvoline 10W30 synthetic oil . At 7,500 miles of suburban driving I stsrted advising him it's time to think about an oil change . His reply was he was going to wait until 10,000 miles - then do an oil change . Needless to say we are in disagreement over the OCI - especially after spending good money to have the engine rebuilt ! At any rate, because he insists on a 10K mile OCI I'm thinking of either moving him into Rotella T6 5W 40 OR Mobil 1 10W30 extended life while still keeping the Fram Ultra oil filter ... Which oil would do better in a jeep 4.0L I-6 if you are pushing the limit to a 10K OCI ?
Rotella T6 5W40 or M1 10W30 Ext Life In Jeep 4.0 ?
- Thread starter ChrisD46
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I would run the bigger filter if you can fit it. My XJ does and I just run it two OCI's
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Nick1994
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It's his car, let him do as he pleases. Just suggest it and move along.
10,000 miles is probably stretching it a little bit, but it'll probably be just fine.
10,000 miles is probably stretching it a little bit, but it'll probably be just fine.
Why was the engine rebuilt?
From my experience T6 will cut the gas mileage by one or two MPG.
I would go with the M1 EP 10W30.
Who did the rebuild? A local shop or a place like Jasper?
I would do a UOA with TBN at least once
From my experience T6 will cut the gas mileage by one or two MPG.
I would go with the M1 EP 10W30.
Who did the rebuild? A local shop or a place like Jasper?
I would do a UOA with TBN at least once
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Thanks - I provided the oversize XG8A (instead of the XG16) for my relative on the last fill - also I should have said : M1 10W30 EP instead of extended life . I hear reports that Jeep 4.0L's are not especially fond of M1 synthetic oils (noisy start up) , I'm just concerned with protection because I don't have to drive it - that's why I am asking about either Rotella 5W40 or M1 10W30 EP as best likely prtection for a 10K OCI ?
T6 definitely butts in on fuel economy.
I'd do Pennzoil syn for that 10k OCI.
I'd do Pennzoil syn for that 10k OCI.
Amsoil XL series group III synthetics are spec'd for 10,000 mile/6 month OCI.
Or if he's really lazy (like I am
) then Amsoil SS with an EaO oil filter for an annual OCI.
Or if he's really lazy (like I am
) then Amsoil SS with an EaO oil filter for an annual OCI.
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T6 definitely butts in on fuel economy.
I'd do Pennzoil syn for that 10k OCI.
I don't know but I switched my sons Jeep with a 5.2 to T6 and mpg came up 1 to 1 1/2 per gal.
got 17 Highway mpg last week on the road with it for 800 miles on sales calls
I'd do Pennzoil syn for that 10k OCI.
I don't know but I switched my sons Jeep with a 5.2 to T6 and mpg came up 1 to 1 1/2 per gal.
got 17 Highway mpg last week on the road with it for 800 miles on sales calls
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The T6 would be a better option IMO, if using M1 I would suggest the HM version instead. Pretty sure the T6 would more likely have a higher remaining TBN at 10k than the Mobil would though.
Originally Posted By: Nitronoise
T6 definitely butts in on fuel economy.
I'd do Pennzoil syn for that 10k OCI.
I don't know but I switched my sons Jeep with a 5.2 to T6 and mpg came up 1 to 1 1/2 per gal.
got 17 Highway mpg last week on the road with it for 800 miles on sales calls
I should have said that applies specifically to the 4.0. I got that too with my 4.0.
T6 definitely butts in on fuel economy.
I'd do Pennzoil syn for that 10k OCI.
I don't know but I switched my sons Jeep with a 5.2 to T6 and mpg came up 1 to 1 1/2 per gal.
got 17 Highway mpg last week on the road with it for 800 miles on sales calls
I should have said that applies specifically to the 4.0. I got that too with my 4.0.
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