You know the scam the government gives us? Driving the speed limit gives you the best gas milage? Well, it seems for my 04 stick shift GT, it gives me the best gas guzzlage. The speed limit on a road I drive every day, is 55mph. It seems that I either have to be in 4th gear at about 2500rpm, it 5th gear at about 1400 rpm. If I understand right, you dont wanna be driving around at a low rpm, especially when there's hills. That means I have to drive at a gas guzzling 2500 rpm for a half hour, or do 65-70. Now I know every type of engine is different. So, what's the low rpm limit for the 4.6? What is a safe level, before you risk doing damage to your engine. Also (and I know this is something everyone would love to know), what rpm range gives the BEST gas milage?