What is the meaning of engine letter codes?

[LylaLee]

Vehicle model numbers consist of three parts: a letter prefix, four digits, and a suffix. The letter prefix indicates the manufacturer of the vehicle. The middle two digits of the four-digit number indicate the main specifications of the vehicle. For trucks, they indicate the load capacity; for buses, they indicate the length of the vehicle; and for passenger cars, they indicate the displacement. Here is additional information: Enterprise name codes: Generally, they are two or three letters, mostly the initials of the company name in Pinyin, such as BJ for Beijing Automotive Company, BK for Beijing Bus General Factory, and CA for FAW Group, which has retained this code. Some companies also use English abbreviations, such as SGM for SAIC-GM.