Cummins B Series engine

From Dodge Wiki
Jump to navigation Jump to search

Also calledISB

The Cummins B Series is a family of straight-4 and straight-6 diesel truck and industrial piston engines. The B Series is known for displacing "one liter per cylinder" because of the popular 3.9 L straight-4 and 5.9 L straight-6. A 3.3 L straight-4 is also available. The B Series is widely used in many segments, including pickup trucks (the Dodge Ram), buses, military vehicles, construction equipment, and marine.

The engine was originally designed by Cummins and Case Corporation for commercial truck applications, and appeared in a light-duty truck, the Dodge Ram, in 1989. This was not the first engine to appear in Dodges as a Diesel option. Mid-70's D models offered the rare, underpowered, Mitsubishi non-turbo diesel. Every Cummins powered Dodge Pickup (since initial production in 1989) has come equipped with a turbocharger. It uses a gear-drive camshaft for extra reliability. Also specified is a deep-skirt engine block and extremely strong connecting rods. A Holset turbocharger is used.

The original B Series was updated with 24 valves and an electronic engine management system to become the ISB in 1998.


The 6BT 5.9 L B5.9 aka the Cummins "12-Valve" was the first member of the "B" engine family to be used in a light truck vehicle. This engine started life in 1984 as an agricultural engine, for use in Case agricultural equipment by a joint venture between Cummins Engine Corp. and Case called Consolidated Diesel Corp. Appearing in the 1989-1998.5 Dodge Ram pickup truck, it quickly became a popular alternative to the large V8 gasoline engines normally used in full-size pickup trucks, while producing nearly double the torque at low engine speeds. Another distinct advantage for the diesel is extremely efficient fuel mileage(also nearly double the gasser).

This engine is also used in the Dennis Dart midibus since 1989 as well as in light to medium sized commercial trucks and buses. It used Bosch Direct Fuel Injection. The injection pumps were VE from 1989-1993 and the famous P7100 from 1994-1998.5, before going to the Cummins Electronic VP44 ISB 5.9 in 1998. In Dodge Ram pickups, the engines produced 160 hp (119 kW) and 400 lb·ft (542 N·m) from '89-'93. They produced 160–215 horsepower (119–160 kW) and 400–440 ft·lbf (542-597 N·m) between 1994-1998.5 depending on year and transmission option.


The 5.9 L ISB (Interact System B) is one of the largest straight-6 engine ever produced for light truck vehicles, and the improved high output 600 version was on the Ward's 10 Best Engines list for 2004.

One unusual feature of the ISB is that it is a multi-valve pushrod engine design. The engine displaces 359 cubic inches (5883 cc) with a 4.02-inch (102.1 mm) bore and 4.72-inch (119.9 mm) stroke. A turbocharger output in the high-compression (17.2:1 in recent versions) Diesel. It is an all-iron engine with forged steel connecting rods, an assembled camshaft, and a cast aluminum intake manifold. The engine is produced in Columbus, Indiana.

There have been several versions of the 5.9 L ISB featured in the Dodge Ram. The BT 5.9 was first introduced to Dodge Rams in 1989. The Cummins engine in 1991.5 got an intercooler. In 1994, the engine changed over to a Bosch model P7100 inline-style injection pump from the previous Bosch VE series rotary pump. Midway through model year 1998, the engine which would now be known as the ISB, was redesigned as a 24 valve model to meet updated emissions requirements and introduced the Bosch VP44 rotary injection pump (featuring electronic control) to the Dodge application. It produced 235 hp (175 kW) at 2700 rpm and 460 ft·lbf (625 Nm) from 1600 rpm to 2700 rpm when paired with a manual transmission, but was slightly downrated when used with automatics.

In 2001, an optional high output (HO) version of the ISB was introduced, producing 245 hp (183 kW) at 2700 rpm and 505 ft·lbf (686 Nm) from 1600 rpm to 2700 rpm when paired with a heavy duty six-speed transmission, the NV5600. The ISB from previous years remained available, and automatic-equipped engines were now rated the same as manuals.

For the 2003 model year, the Cummins was introduced with Bosch high pressure common rail fuel injection, again increasing power output. Midway through the 2004 model year, the Cummins 600 was introduced, producing 325 hp (242 kW) at 2900 rpm and 600 ft·lbf (813 Nm)at 1600 rpm. This high torque output gives the engine its name, and also offers a high specific output of 102 ft·lbf (138 Nm) per liter of displacement (1.67 ft·lbf/CID)

A 610 version, new for the 2005 model year, pushes torque to 610 ft·lbf (827 Nm).


The 3.9L/4BT Cummins is an engine in the same family as the 5.9L Cummins turbodiesels. The 3.9L/4B is an inline four-cylinder turbodiesel that was popular for many step van applications including bread vans and other commercial vehicles. This engine is also used in various industrial and construction applications. With a cylinder bore of 4.02 inches (102 mm) and a piston stroke of 4.72 inches (120 mm), the engine had a wet weight of 745 pounds (338 kg). In recent years it produced 130 hp (97 kW) and 355 lb·ft (481 N·m) of torque.


The B6.7 is the latest version of the B Series. It is currently the largest inline-6 engine produced for a light duty truck. It produces 350 hp (261 kW) and 650 ft·lbf (881 N·m) in the 2007.5 and newer Dodge 2500/3500 pickup trucks with the Chrysler built 6 speed 68RFE Automatic Transmission built at the Kokomo Transmission Plant in Kokomo, Indiana. Engine output is slightly reduced with the Mercedes G56 6-speed manual transmission at 305 hp (227 kW) and 610 ft·lbf (827 N·m). The 2007 and newer 3500 Cab & Chassis trucks only get the 305 hp (227 kW) and 610 ft·lbf (827 N·m) version of the B6.7 whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission. As for the 2008 4500/5500 medium duty Chassis Cabs or the Sterling Bullet Trucks, they will also receive the 305 hp (227 kW) and 610 ft·lbf (827 N·m) version of the B6.7 whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission.

There are many changes over the previous B5.9 for the Dodge truck, the most obvious being the larger displacement. The B6.7 had an increase of bore and stroke to 107 mm (4.2 in) and 124 mm (4.9 in) stroke, respectively. It includes a cooled EGR system, variable geometry turbocharger, a new higher-pressure version of the Bosch direct-injection fuel system, and a particulate filter designed to reduce diesel particulate matter by more than 90%. "Cummins PDF bulletin 4106307"PDF (1.13 MiB). Still, it retains 45% of the original 5.9 components.

The Dodge trucks' B6.7 competes head to head with V8 engines offered by General Motors and Ford Motor Company, the Duramax and 6.4  Power Stroke, respectively.

Both the B4.5 and B6.7 are used in DAF Trucks' LF45, and LF55 and CF65 range respectively.

See also