Rep Power: 286

youre proving that you dont know anything about turbos. wheres this ad? where do you see greddy recommending a thicker oil? turbos, large or small, do not require a thicker oil. ask the guys at forced performance, turbochargers.com, any well respected company. i owned a turbo car before my civic, ive done tons and tons of research on turbos and not once did i ever see a recommendation for thicker oil because someone was upgrading their turbo.

 
Rep Power: 282

I never claimed to be an expert on trubos, but i do know somethings.
This is going nowhere...

 
Rep Power: 286

i agree that this is going nowhere, so im just going to leave a few final thoughts.

youre right that the threat of a oil breakdown from heat on a turbo'd engine is very real. so i would see no harm in running a 5w-30 or 10-30 if it'll make someone feel better. but personally, i wouldnt run any thicker than that. the fastest way to kill a turbo is to provide inadequate oil flow to it. and oil pressure would be a major concern of mine by running a very thick oil in a car which specs 5w-20. thats one thing many turbo mfg's are all very clear on, oil pressure that turbos require. many dont say much about oil weight, but they all agree that the turbo must get at least X amount of oil pressure.

 
Rep Power: 361

lol here in PA we get 100F+ days and 0F- days so its pretty much 5w30 for everyone