The 3.9L or 4BT Cummins diesel engines are designed for light duty vehicles and small commercial equipment. The 3.9L/4B is an straight or inline 4 cylinder turbo-diesel engine that was popular for many step van type applications, including milk trucks, delivery vehicles, service work trucks and other less known commercial applications. It is also the small brother of the 6b engine, which are the engines in Dodge 3500 and 2500 diesel pickups.
The 6BTA5.9 L B5.9 was the first member of the Cummins “B” series engine family. Which was to become known for the one liter per cylinder design to be used in a passenger vehicles. This engine and its cousin the 4BT3.9 was introduced in 1983 or 84 as a part time truck engine and part time agricultural engine designed for use in Case agricultural equipment. A combined effort in resources between Cummins Engine Corp. and Case called Consolidated Diesel Corp is the name of a joint venture between Case and Cummins diesel to produce said engines.
The engine was originally designed by Cummins with the help of Case Corporation for commercial work equipment used to power stationary equipment like power generators as well as light and medium duty truck applications. The first mass production agreement was for the engines to be used in Dodge pickups as their first venture into diesel powered vehicles.
The model year 1989 was a first for Dodge Ram pickup trucks. The engine has been used in nearly every way imaginable from boats, farming purposes of all sorts, industrial and commercial tools and service equipment, conventional and passenger vehicles too. It has stood the test of time, literally and proven to be one of the most widely used engines ever produced.
The original US plant in Rocky Mount, NC was still was operating in 2007, where the first production B engines were manufactured as a joint venture with Case. Later the Walesborough, Indiana plant re tooled their equipment to produce the Dodge engines also. Currently (as of 2007) the total production of 4b and 6b engines combined is over 1000 engines per day from both facilities. Also, the engine is built in the UK & Brazil (possibly other locations in the world).
Some of the newer 4b version QSB (electronic controlled) that are built in Brazil and go in the Ford F150 trucks. Contrary to many beliefs, the computer controlled diesel engines are every bit as complicated as a late model luxury car gas engine. In fact they run so smoothly it’s hard to detect a diesel engine except for more external engine noise.
Diesel engine jargon is different than gasoline engine jargon. Make sure you buy diesel engines from an authority or suffer the consequences of getting the wrong engine for your application or maybe a bad engine. Diesel engines have been an enigma to many people for a long time. We have a department set up for diesel engines by diesel engine people. Want to buy the right diesel engines? Call GotEngines.com @ 1-866-320-1065.