I am torn.

[webfors]

If you're scared of 40 weights use GC. It sits nicely between your average 30 weight and a 40 weight and doesn't shear like some 40 weights.

 

[chevrofreak]

The spec sheet I found for some 40W-70 put the 40C viscosity at 291. That's 6x the viscosity of a 5W-20! That's just absolutely insane!

 

[sprintman]

No it isn;t, it just seems so to some like you who have limited oil knowledge. I guarantee to run 40W70 in the Mazda next summer and open to any one who wants to witness it (supercheap air fares, good excuse for a holiday Downundwer). Will send it to Terry Dyson for used oil analysis afterwards.

 

[il_signore97]

^That would be awesome. Would love to see that UOA...