I have been using Mobil 1 10w30 for the longest... I'm thinking of changing to 0w40 as it's thicker but still has good cold start properties. What do you guys says? I think 15w50 is going to far but would the 0w40 be good or should I stick with the 10w30???

I run Mobil 1 synthetic. I'm pretty sure it is 5W/30...

Mike M

If you built the motor as a blower motor with a little looser clearances than I would use 15-50 . If you have a stock bottom end I would stick with the 10-30. I'm using Mobil 1 10-30 in the winter & 15-50 in warmer weather.

10w30 is it... only thing is the mobil 1 10w30 is very loose, comparable to other 5w30's... the mobil 1 5w30 looks like water when you pour it in. That's why I was thinking 0w40 as some have said it's closer to an actual 10w30. Comments?

I run 15-50 in my car and have had good results, I used to run 10-30 though. Both Mobil oils are good.