The cost is typically going to be in the range of $3,000 to $5,000. The main variable there is the size of the propane storage tank that you're adding to the vehicle. In both kits, the LPG is added after the air filter and prior to the turbo, so it blends in with the air, so it goes into the engine with the air, and the diesel fuel goes in through its own current injection process.
On June 7th, 2012. See this statement in context.