5w-30 vs 10w-40

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with my oil pressure fluctuating someone suggested using 10w-40 instaed of 5w-30? is this bad advice? 2005 nissan frontier nismo 6 cylinder
 
Considering that you live in Louisiana it won't make much of a difference.

Go for it, I guess.
 
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stock gauge... when i stop at a red light it goes just above the L and goes just above middle when driving? never reaches H level
 
10W40 won`t hurt a thing. Is this a VQ? I know the VQ Maxima`s FSM lists anything from 5W30-20W50.
 
Originally Posted By: aquariuscsm
10W40 won`t hurt a thing.


What about startup wear? That 10W-40 takes a full 5 minutes to reach all
the bearings on startup, but 5W-30 only takes 2/100ths of a second.
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Originally Posted By: Merkava_4
What about startup wear? That 10W-40 takes a full 5 minutes to reach all the bearings on startup, but 5W-30 only takes 2/100ths of a second.
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Of course, there's always that issue of immediate, catastrophic wear.
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Aside from that, while CATERHAM has eloquently stated his case for 10w-30 being an obsolete synthetic grade, I'd argue that 10w-40 is about as obsolete a grade as one could possibly imagine, particularly in conventional. It was terrible oil years ago, and while oil certainly has improved, specifications have changed.

Any vehicles that currently specify a 40 weight oil are either diesels which spec HDEO (10w-40s tend to meet older diesel specs, not modern ones) or European cars, which have their own specifications, which the run of the mill 10w-40 certainly cannot meet. I can't think of any mainstream vehicle currently being sold in North America that would call for 10w-40 as the preferred grade in the manual.

For something well out of warranty that is speced for a 40 weight oil, 10w-40 would be at the bottom of my list of choices, unless it was dirt cheap. Up here at least, 5w-20, 5w-30, and 10w-30 are the grades that go on sale. So, my old truck and the Audi got 15w-40 at a much more attractive price than what 10w-40 goes for.

I know it takes 5 minutes for 10w-40 to reach all the bearings on start up, and probably double that for 15w-40, and maybe triple that north of the border.
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The 15w-40 was cheaper though.
 
It will still fluctuate, but in a different range.
Oils viscosity changes when hot/cold, and different RPM affect the pressure also.
 
Originally Posted By: awoess
stock gauge... when i stop at a red light it goes just above the L and goes just above middle when driving? never reaches H level


Does your check engine light come on? If not I suspect you do not have a low oil pressure.
 
Originally Posted By: dave1251
Originally Posted By: awoess
stock gauge... when i stop at a red light it goes just above the L and goes just above middle when driving? never reaches H level


Does your check engine light come on? If not I suspect you do not have a low oil pressure.


I'm yet to see a "check engine light"(the amber one operated by the PCM), that was triggered by low oil pressure... A low oil pressure light will be red and operated by a sender that connects directly to the light circuit...
 
my check engine light does NOT come on.... i think i'm over reacting a little bit? thanks for the advice.. i'll stick with 5w-30 Royal Purple
 
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