2 mazdas 1-turbo 1-v6 same oil?

[whitson01]

i have a 05 mazda 6 v6 with around 120k miles factory recommended oil 5w20. and i have a 11 mazda cx-7 with around 5k miles factory recommended 5w30. i normally use amsoil, PU or PP. so i was wanting to just keep 5w30 at home for both cars. any problems with this? basically im looking for best protection and gas mileage. what if i went the route of something like 0w30 or rotellas t6 5w40? thanks for any help.

 

[dparm]

Nothing wrong with 0w30 in both, though it will sap some MPG on the 6.

Rotella would be way too thick.

 

[Eddie]

+1 FOR 0W30

 

[chevman4life]

You won't notice any difference in MPG. I don't and I use it vs. 5w20. If there is any difference you won't even notice it on paper.