The rule is any USED vehicle which is equipped with the necessary Federal Emission Components is eligible for California registration as long as the vehicle's exhaust emissions fall within California's limits and the vehicle's emission system has not been tampered with. This rule does not apply to new out-of-state cars or trucks.
In this specific case since your Dodge 2500 is obviously considered a used vehicle it is eligible for California vehicle registration, and is allowed to participate in the smog check inspection process without any engine upgrade or modification. If its emissions fall below California emission cutscores, and the engine has not been tampered with it can pass the emissions test.
