There's no reason to use a 10W-40 oil in anything besides a lawn mower. You don't want an oil that's thicker at startup than a 5W. If you live in a very hot climate and temps never drop below 70 degrees, it won't make much difference. But up north, stick with 5W & 0W where allowed by the application.
A 5W-40 would also be good for a turbo application, as by the time it shears, it'll be down to a 30 anyway.