We all complain about the fuel mileage of our trucks. My 5.3 with AFM gets about 18.5mpg if I try really hard-and I do. That's great because it's what my '99 4.2l Ford got with a 5-spd. But does anyone understand the hydrogen fuel cell well enough to install it on their own vehicle? There's a mechanic in our area claiming he can get you 50% better fuel economy on any vehicle using it.

Has anyone on here tried it? Everyone on the internet wants to sell you plans or a very expensive prebuilt kit. And I would imagine it would void the warranty of an '08 Silverado. Can you imagine getting 27-28 mpg with a 5.3L? That would be awesome. It would get better milaeage towing a boat than it does unloaded now.

I wish I still had my Mustang with the carbureted 289 to play with. Or even one of the 4-cyl trucks I've traded in over the years. They might be capable of 42 mpg!