Cyclic Hardover

What kind of difference do you have with 10-30- over 5-30?

c2vette

If it is not clear by now, I hope all the SS owners know by now that synthetic is standard and absolutely required. The turbo motor sprays oil on the underside of the piston for piston cooling required by high boost pressures. You will likely void your warranty if you use non-syn for an oil change in an SS.

Black Rose

I read on the GM Powertrain site that the 2.4 VVT motor does this as well.

"Targeted oil jets to cool pistons" is the wording they use.

Lone Ranger

Hey I want my lowly 2.2 to have piston oil jets, too!

Cyclic Hardover

I'm curious as the difference in engine performance from 5-30 over 10-30?

Offy

The engine tolerances are the major driver of oil viscosity needs. The tolerances of the new engines are growing closer every day and the oils are constantly getting better (except for the zinc but that's another issue). Back in the day thicker was usually better but the opposite is closer to the truth today. I would refrain from going to a higher viscosity than recommended. Exceptions may be very hot climates with extended highway driving. Even then I would abide by the low viscosity (first stated) number.
Turbo assisted motors are usually hotter running and almost always require synthetic for gasoline engines as it dosen't burn as easily as dinosour oil.

Cyclic Hardover

I do like your explanation here. Is it better for the engine or better for the engine due to climate?

I'm geared more towards the climate issue since I have experienced a few of them aroud the world and do make sense to me.

New engines can tolerate a lighter oil but is it strictly for the engine or does climate play a role in the oil with newer engines.

I have seen first hand what 10-40 does in Fairbanks if you know what I mean I'm not questioning but trying to accept new technolgy.

It's like oh this engine runs best on ______. Well may so but should it be used where We live in the world

Leon

Several of the vehicles in my stable recommend 5W30 but also list 10W30 if the temps don't go below 0 degrees. I run 5W most of the time, but if I get a bargain on my favorite brand, I'll put 10W in it.

Cyclic Hardover

I'm running 10-30 and I do not see a problem here in New Mexico. Even in the winter it does get chilly but not worth 5wt

NickHHRSS

The first number means that it gets tyhinner in cold weather and thickens up to the second number when warmer. When you live in SoCal and Never even see the freezing point in the dead of winter, 5-30 works no better or worse than 10-30.