Put in Mobil-1 and tufoil today

[regor]

3000 miles later and still no difference in MPG, in case anyone wanted to know.

Engine does run smoother and cooler.

[nascarnation]

Originally Posted by regor

3000 miles later and still no difference in MPG, in case anyone wanted to know.

thanks for the followup
no reason to think it should
viscosity is viscosity

if an oil change could add 1 mpg, the mfgrs would be all over it

but for the oil producers, it is a triumph of marketing