Originally Posted By: badtlc
Originally Posted By: Tater
Is there a reason you are using 5w-30? I am using 5w-20 in my speed since the manual calls for it.
You might double check the owner's manual if you really do own a turbo charged MazdaSpeed.
5w-20 was a mis-print. It's definitely 5w-30. Most MZR owners are seeing UOA's show shearing to 20w anyhow, as mine has done on last 2 reports. Wear numbers have been good, so not sure the shearing is necessarily a problem.