I'm in the process of going through the list of options for my new truck, a gas engined F-350 Lariat SuperCab with an honest to goodness 8 foot bed. According to a couple dealers I have talked to, such a truck has never been built by Ford, even though it's a mathematical possibility given the 2014 order guide.
So my question is this:
Option code 98F is the CNG/LPG Gaseous Engine Prep Package. According to the description it includes hardened intake valves and valve seats. For me I don't ever plan on converting the engine to propane but I wonder… Would the hardened valves and valve seats be an advantage for longevity in a standard unleaded gas engine?
My 460 powered '94 F-250 with 248K miles is still going strong after 19 years and I'm hoping the new truck will last as long.
The reason for the hardened valves/seats is because, in a CNG/LPG vehicle, no gasoline flows over the intake valves to cool and lubricate them. This means you often end up with valve recession/burnt valves if you don't use a valve designed with CNG/LPG applications in mind.
Whether or not it would help with the longevity of a gasoline-only engine, I couldn't say. They don't clarify exactly what they mean by 'hardened', be it a coating, a different alloy, etc. Often times there is some kind of tradeoff. You might get a more temperature resistant valve, but unfortunately you also get a valve with less wear and corrosion resistantance.
If it was me, I would probably go for it. Not necessarily for longevity reasons, but because, when it comes time to sell the truck, it could add to the resale value (as well as increase the potential pool of buyers). Who knows, maybe in ~15 years lpg/cng conversions will be the norm. You just don't know.