Question, we have a 2019, 4500 4x4 Cab and Chassis crew cab and also a 2020, 3500 Mega Cab 4x4 both with the 6.7. The 4500 Cab and Chassis says B-20 Bio Diesel Capability, but my 3500 does not say it has the same capability. What makes the 4500 6.7 Bio diesel capability and my 3500 not?