Most BMW’s have identifying Model Numbers on the rear of the trunk lid or in other locations, like this:
The "5" refers to the Series, the 5 Series.*
Other current Series numbers are 3 and 7. Series 6 and 8 were used in the past. BMW has announced a 1 Series future model.
The "30" refers to the engine displacement, 3.0 liters.*
Current models run from 1.6 in the 3 Series Compact to 5.0 in the 7 Series Sedan. These numbers are not always accurate; the E30 325e and the E28 528e had the same engine, a 2.7 liter!
Many model numbers have a suffix, like "d" in the picture above.*
The "d" refers to a diesel engine. A popular suffix is "i", which originally referred to an Injected (fuel-injected) model, but has come to represent BMW performance, and it is applied to a number of models.*
Here are some other common suffix codes and what they mean:
s = Sport model
These models have sporting options like bigger brakes, stronger suspension, etc.
e = Economy engine
Technically, "e" refers to the Greek letter "eta", which means "efficiency". The eta engine was used in the 325e and 528e models.
t = Turbo charged engine
When used alone, "t" can refer to gasoline or diesel models. The "td" stands for " turbodiesel" while "tds" refers to " intercooled turbodiesel".*
t = Touring
For early models,*" touring" could refer to hatchback, wagon, or even sport versions.
x = All Wheel Drive model
The original model was the E30 "ix", but the latest E46 3 Series AWD model is designated "xi".
L = Long wheelbase model
Examples include the 7 Series Sedan, 750iL. Sometimes, "L" is used as a prefix, like the "L6" and "L7" models. These models are not only long, but they are also premium models, usually with extra luxury features.
C or c =*Coupe
Sometimes used with an "S", like "Coupe Sport". The "C" code is often used for luxury coupes like the 6 and 8 Series. The new E46 3 Series uses the "C" code, too.
A = Automatic*transmission
Rarely seen, for BMW does not often advertise automatic transmissions! A common example is "525iA".