I just switched to M1 OW40 on my last oil change. I'm about 500 miles, and it seems to be working pretty good. High rpm acceleration seems to be improved. The engine seems to be much smoother in the higher rpm ranges, and it seems quieter at idle.

My mileage is much improved also. I'm at 350 miles or so on this tank and I'm still on half full. I drove slower than usual last weekend on a road trip, but I also had quite a bit of in-town driving.

Do we have any long term users of this oil on here? How's it working out for you?

 

M1 0w40 is a great synthetic oil...Much better than their 5w30 & 10w30 lines... Along with that, Castrol Syntec 0w30 (German made stuff!!!) has proven in many oil analysis test to absolutely rock! That is what I run in my LT1 and love it. In actuality, it is basically a true 40 weight oil FYI...

Can't go wrong with either in a daily-driver high performance car like ours that is probably driven pretty hard...

Mike

 

Did you upgrade to a 45 gallon tank?

-brent

 

LOL, you know how our gas gauges are. The needle in on 1/2, but it's actually more than that.

I would try some GC 0w30, but I haven't found any here yet