I use Mobil 1 synthentic 5W30 in the truck all year round, I was just wondering if you guys use the same? Or do you go with a 10W30 in the summer or something...

Thanks

 

year round here

 

year round here too.....well almost a year soon....heh

 

Year round

 

Two years and +33k miles so far.

 

If you've been using 5w-30, then switching to 10w-30 offers no benefit, as they will both be a 30 weight at operating temperature. The 5w will be beneficial at startup, especially in the winter. Their isn't a huge amount of difference between a 5w and a 10w.

 

Royal Purple makes a 5W20. Ive been using it since 5000 miles.

 

Max, you are alittle backwards there. Oil is at it's thickest when it's cold! The oil would be a 30W at startup then thin-out to a 5W or a 10W when it is up to temp. I have never seen oil get thicker when it heats up??

 

Not now:

http://www.econofix.com/oiltypes.html

See second para.

Dan

 

Ok, I stand corrected.
However, I do stand by what I said as far as oil not becoming thicker at temp, this is true, it just thins out less due to the polymers.
Oil weight is actually determined at 0*F(the W part of the grade), then the polymers keep the oil from thinning out as much as a 30W or a 40W or 50W would at operarating temps. Multi-grade oils are thin oils with polymers added, that act like thicker oils would when hot, in other words they only thin down as much as the higher number in the equation oil would.
If anyone has ever changed their own oil, they would know that oil is supposed to be changed hot(as it is thinner then)and flows/drains better than when it is cold.
Bottom line is a 40W oil and a 10W40 oil still becomes very thin when hot, but both are equally thin at temp, they are not a 40W at 100* As oil thickness is not rated at high temp. The difference is at 0* the 10w40 is a 10W oil and the SAE 40W would still be a 40W.

It just seems like everyone thinks that an oil actually thickens up when it gets hot and that really gets me going!


http://www.vtr.org/maintain/oil-overview.html

This is also a very good article.

 

Viscosity info:

http://216.239.53.100/search?q=cache...n&ie=UTF-8</a>

It can get confusing:

Both Exxon and Shell develop, manufacture, market and sell additives used in the production of fuels and lubricants, including viscosity index improvers used in lubricants for crankcase applications (“motor oil” or “engine oil”.) Viscosity index improvers (“VII”) (also known as “viscosity modifiers”) are added to motor oil to improve the ability of the motor oil to flow properly. The viscosity of a fluid is its internal resistance to flow; the higher the viscosity, the more resistance to flow. The viscosity of lubricating oil is affected by temperature, higher temperatures lowering the viscosity. Motor oil must have sufficient viscosity to adhere to the internal surfaces of the engine even after the engine temperature rises and reduces the oil’s viscosity. Motor oil must also have low enough viscosity to flow through the engine when the engine is cold, particularly in winter weather. Viscosity index improvers give motor oil the ability to have the appropriate high viscosity at high temperatures and the appropriate low viscosity at low temperatures.

Dan

 

Thanks for the replies guys