Anyone ever use Mobil 1 15W-50?

What AdRock said!

Forgot the 50 weight oil. Way too thick! Even a 40 weight is overkill for 99% of the applications in these engines.

One obvious exception where you could use a heavy oil is during SUSTAINED operating conditions, such as open-track/road-racing events where the oil is suspect to breaking down due to high temps/high engine loads. We're talking 20 minute, 40+ minute endurance sessions here...and the oil has to be changed before the next session due to it breaking down during these types of events.

:cheers:
 
yep, agree

Although I am new to the site, I have spent a lot of time researching oils. I friend of mine worked for Ford in Detroit and did a bunch of work on how different weight oils affect dyno's. I have learnt a lot from him

I would go mobil1, 5-30, easy to find....