engines
Everything has flaws, it really comes down to preference. In my opinion the 4.6 has less issues, but the 5.4 makes more power. And as for gas or diesel it really depends on what you're using your truck for, you'll hear alot of people say the 6.0 powerstroke isn't a good motor, and they're right it's not a good motor for someone who doesn't treat it like a diesel motor. I've always wanted a diesel but prefer the maintenance costs of a gas and also it's nice not having to warm my truck up in the morning

