What are the differences between National V and National VI engines?

[DeJohn]

The differences between National V and National VI emission standards are as follows: Different emission standards: The National VI emission standard is more than 30% stricter than National V. Excluding the influence of working conditions and testing, gasoline vehicles' carbon monoxide emissions are reduced by 50%, total hydrocarbons and non-methane hydrocarbons emissions are reduced by 50%, and nitrogen oxide emissions are reduced by 42%. Different implementation times: The National V standard was implemented nationwide on January 1, 2017. National VI has been implemented since July 1, 2019. Different principles: During the National V phase, diesel and gasoline vehicles had different emission standards, but National VI adopts a fuel-neutral principle, meaning the emission limits are the same regardless of the fuel type. Different issuing departments: The National V standard was issued by the Ministry of Environmental Protection. The National VI standard was issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection and Quarantine. Different letter representations: National V is represented by "V," while National VI is represented by "VI." Different monitoring requirements for plug-in hybrid electric vehicles: Compared to National V, National VI has improved monitoring requirements for plug-in hybrid electric vehicles, including energy storage systems, thermal management systems, brake regeneration, drive motors, generators, and other regulations. Different prices: National VI vehicles are equipped with more components than National V vehicles. Additionally, automakers incur extra costs from vehicle declaration tests and production, leading to significantly higher prices for National VI vehicles compared to National V. Different scrapping timelines: Although the government has abolished the scrapping age limit, older vehicles may be banned from roads, effectively rendering them scrapped. For example, a National V vehicle purchased in January 2019 and a National VI vehicle purchased at the same time may both have a 15-year registration, but their actual usage will differ. For instance, National III vehicles from 2010 and National IV vehicles from the same year can still operate in Beijing, but as more cities impose restrictions, many older vehicles become practically scrapped. Thus, even for vehicles of the same year, their usable lifespans differ. National V standards are as follows: Gasoline vehicles must not emit more than 1,000 mg of carbon monoxide per kilometer driven. They must not emit more than 68 mg of non-methane hydrocarbons, 60 mg of nitrogen oxides, or 4.5 mg of PM (particulate matter) per kilometer driven. National VI has two standards: National VIa and National VIb, as follows: National VIa standards: Gasoline vehicles must not emit more than 700 mg of carbon monoxide, 68 mg of non-methane hydrocarbons, 60 mg of nitrogen oxides, or 4.5 mg of PM per kilometer driven. National VIb standards: Gasoline vehicles must not emit more than 500 mg of carbon monoxide, 35 mg of non-methane hydrocarbons, 35 mg of nitrogen oxides, or 3 mg of PM per kilometer driven. Under the National VI emission policy, although National V vehicles are not currently restricted from normal use (no driving bans or license plate restrictions), their resale value will be significantly affected. For truck owners, if they purchase a truck on loan for freight transport, the vehicle's depreciation after paying off the loan represents the net profit during that period. A higher residual value means more profit for the owner. From this perspective, National VI vehicles, with longer lifespans and greater road access, offer more advantages.

[MelanieFitz]

I've been driving trucks for twenty years, and I clearly felt the engine's temperament change when switching from China V to China VI. China VI vehicles are particularly picky about fuel—you must fill up at reputable gas stations, as fuel from small workshops can easily clog the particulate filter in the exhaust pipe. Manufacturers packed more purification devices into the exhaust system, like upgrading the catalytic converter to a dual-layer one, and the piping under the car is more complex than a spider's web. The most annoying part is that the vehicle now self-checks emissions, with several extra sensors on the exhaust pipe—if you're not careful, the fault light comes on. Old Wang at the repair shop says China VI engines are tuned to be gentler; stomping on the gas doesn’t give the same kick as China V, but in the long run, it’s definitely more eco-friendly.