Mobil1 Extended 15000 miles?

[ConElite]

I put in 5 total and check the dip stick...it's right on. I've always put in 5 quarts...should I be putting in 6 quarts? I read 5.5 is what is recommended, but buying an extra quart only to put half doesn't add up for me...5 quarts and she's right on...I just might do 6 quarts then.

When I was the lube tech. At the Chevy Dealer We were told to Put 6 total on the LS1. The Corvette's 6.5. I have been putting 6 in every oil change. I recommend 6 quarts and you should get out right around 5.4-5.8 quarts back. I run 10w30 during the winter and i run straight 30 during the summer b/c it gets rather hot during that time of year.

[Christopherrr]

When I was the lube tech. At the Chevy Dealer We were told to Put 6 total on the LS1. The Corvette's 6.5. I have been putting 6 in every oil change. I recommend 6 quarts and you should get out right around 5.4-5.8 quarts back. I run 10w30 during the winter and i run straight 30 during the summer b/c it gets rather hot during that time of year.

10w30? Isn't that too think, especially for the winter? I always though you run thicker oil during summer months and thinner oil during colder months. But from what I've learn, the viscosity of 5W30 and 10W30 are teh same once it warms up...

[Injuneer]

The "lube tech" above doesn't appear to have any idea what the viscosity ratings of multi-viscosity oils means. For "winter", you want the first number to be "lower". The FACTORY engineers recommend 5W-30. That means on a very cold morning (0degF) the oil exhibits the viscosity of a "5" weight oil, remains thin at that low temperarute, and starts to circulate VERY quickly, protecting your engine from damage on cold start. A "thicker" oil would not circulate as quickly, leaving your engine subject to damage from inadequate oil circulation.

Even in warm weather, you want a thinner oil on cold start. The FACTORY engineers allow you to opt for a 10W-30 in warmer weather. Than means you still need the flowability of a light weight, thinner "10" weight oil to get it flowing fast enough to to protect the engine on cold start. That is when 80% of the engine wear occurs.... on cold start. The ABSOLUTE WORST thing you could do to your engine is to run a SINGLE VISCOSITY 30-weight oil. It will not provide adequate cold start circulation. If you don't understand why a 10W-30 oil has exactly them same viscosity as a straight 30-weight oil at 100degC (212degF), you shouldn't be ignoring the engine manufacturers' recommendations.

If you don't truely understand the meaning of 0W-30, 5W-30, 10W-30, etc, do yourself a favor and follow the engine manufacturer's ratings EXACTLY. And this advice is coming from a licensed professional engineer (licensed for 36 years), who spent a combined 17 years working for the world's largest oil company, in their central research and engineering department, and in the distribution system. The auto manufacturers' engineers are a lot smarter than you give them credit for being.

[SOMSS]

Finaly someone that actually knows what they are talking about.

[ryan34]

Finaly someone that actually knows what they are talking about.

So is that a shot at everyone else that responded or something?

[ConElite]

Well I guess it matters where you live. The chances of us over here in So. Cal. seeing anything lower then 40 degrees is not at all commen even during the winter, and summer temps of around 90-103 degrees during the summer.
So I would understand a 10w-30 in the winter, but I guess as Injuneer said above, We should never run a "SINGLE VISCOSITY 30-weight oil."
Learned something, thank you.