UrSoccer_mobileĀ®

What would be the ideal wieght to use in the Pacific Northwest where the weather is pretty mild. Not too hot summers and not too cold winters.. I am running 10W30 synthetic blend right now and would like to venture into the full synthetic world.

So far, no leaks and no oil consumption as far as I can see.

TIA

TIA

Sloooo4esT

what does the first number mean Xw40

UrSoccer_mobileĀ®

temp?

Tornado //S6

How thick the oil is when the engine is cold(just started). Lower=thinner

Sloooo4esT

thanks, i think i understand it as commen sense but just checking.

bluevr6

weight is roughly equivilant to viscosity (different scale).....

Tornado //S6

It's how thick it gets when the oil is warmed up...again, higher=thicker

Bill the Cat

Using 10w - 30 as an example.

The lower number is that the oil is the same 'thickness' as a 10 weight at 0°f, and the same thickness as a 30 weight at 200°f. The oil is thinner at 200° than at 0°, however.

To make a 10w - 30 out of dino oil, start with a thinner oil, say 5w, and add 'viscosity improvers' to get the desired results. (5w anything is downright horrid stuff.) These 'improvers' are not as stable as the oil part, or provide the same lubrication. Meaning, multiweights needed to be changed more often, and the 'wider the spread', the less oil there is in a quart. (Which is why a 10 - 30 is a better choice than a 10-40 in a high output/heat engine.)

With a synthetic, toss the whole 'improvers' theory out the window - they can brew up what ever they want - and it will all be lubricant. And a damned good one at that.

The thinner the oil when cold, the faster parts are lubed at startup. The thicker at full temp - the better for oil pressure. (BUT - robs HP!)