I know this sounds kinda dumb, but I was wondering about mobil one oil. I have always uesd Mobil 1 10-30 but I was wondering if I should be using 5-30? The owners manual says either is perfectly ok? just wondering what you guys think?

 

5-30 here.

 

It depends on temperature and operating conditions in your area.

 

I actually use 20W 50 Mobile 1 in my SC Forged motor - LS1 347 CID! and used it on the stocker before as well!

Thanks,Matt

 

I think most P.A are using 5-30 from my limited experience.

 

I use 10-30 but I also use royal purple as my oil of choice.

 

5-30 is the oil of choice for most areas

 

I think the majority of C5 owners use 5-30. Another topic that will bring a rash of different opinions.

 

5W30 is preferred... Use it in all my vehicles...

 

5-30 here too.

 

If you don't drive in the winter, then 10W-30 is fine. When I lived in Florida that's what I used but now use 5W in NE just because I'm in broader temp range and my take it out during the winter.

If you look at the specs of M1 5W and 10W there's very little difference.

 

Since you live in PA, 5W30 would be the better choice, simply due to your cold winters.

 

I spoke to a Mobil 1 technical specialist a while back about this very topic. He told me that essentially, 10W-30 Mobil 1 is not needed (obsolete). He went on to say that even at 70 degrees F, 5W-30 flows through your engine faster than does 10W-30 and since startup is when most of the wear occurs to your engine internals, 5W-30 is the better choice. He went on to tell me that he, himself uses 0W-40 in Texas, where it gets fairly hot.
In summation, stick with 5W-30, 0W-30, or 0W-40 synthetic oils (non-heavily built LS1s or LS6s); your engine will last longer, all other things being equal.

 

Thank You! The last few winters have been pretty mild, it gets down to 10 degrees for mabye a day or two but mostly is at 18 to 25 in January and february but I don't drive all that much and change to oil once a year, so Mobil 5-30 is most likely the best choice !

 

HI Jim,
Here in central pa. not to far from you, its 5w-30
robsc501

 

Just an observation... my daily driver Honda CR-V manual shows one, and only one recommended oil, 5-w20. The engine is just 2.4CC, and typically (for Honda) high-reving. The point? I think advances in metalergy and the closer tolerances in modern engines is reason for us to reverse old notions about engine oil. I used to always worry about my oil being too thin to protect. (remember when 20W-40 was commonly used in new cars?) Now maybe we should be concerned about using an oil that is too viscus (is that the right word for thick?) to circulate quickly on cold startup, where major wear can occur.

 

Man, that thing must be slow...

To the OP, I use 5W-30 here in the DC area, and our climates is pretty similar to yours. Because I have summer tires on the car all year round, I don't drive it if the temp is any lower than 35-40 degrees anyway.

 

[QUOTE=rcs128;1565170170]Man, that thing must be slow... /QUOTE]

Geez, does CM sound any better? Anyway, about 144 CI. Still slow compared to my C5.

 

The trend is definitely moving towards thinner oils, and there will be a time soon when all cars come with 5w20 or 0w20 as the specified viscosity, and we'll be referring to 5w30 as the thick oil!

When an engine is designed to run on 5w20, it's perfectly safe, and you won't kill your engine with that viscosity. As strange as it sounds, a lot of people refused to run 5w20 in their engines, thinking it would cause them an early death, even if the owner's manual called for it. But guess what, these engines running on 5w20 are not failing early like many naysayers thought! Even under hard use, such as police cars, or people that do a lot of towing in high heat, these engines are going 200,000 miles and beyond. And the oil analysis results on these engines are proving that engine wear is good. In fact, I've switched my wife's 2000 Civic over to 5w20 and the oil analysis results are excellent. Her owner's manual originally specified 5w30, it was the last year Honda called for 5w30 in the Civic, but they later released a TSB saying the 2000 Civics could run 5w20. Her engine turns over faster on a cold morning, and even revs a little more freely with the thinner oil.

 

Damn..Id do ANYTHING to get my wife's "engine" to turn over faster on a cold morning..getting her to "rev a little more freely" would be nice too!!!!