In 1989 Chrysler partnered with Cummins to produce the first-generation 5.9L Inline 6-Cylinder Turbodiesel, also known as the 6BT Cummins-powered truck. This engine was originally used for agricultural applications, but the durable design made it the perfect option for Dodge’s heavy-duty pickup trucks. The 5.9L Cummins can be found in the Dodge 3/4-Ton (250 Series) and 1-Ton (350 Series) pickups equipped with Dana 60 front axles and either the Dana 70 or Dana 80 heavy-duty rear axles. The First Gen 5.9L Cummins offered features never seen on a diesel pickup before, including direct fuel injection and a turbocharger. These new innovations helped create the new standard for OEM diesel performance while completely revitalizing Dodge’s truck lineup.
The 1st generation Cummins was designed with durability and simplicity in mind. By using an inline 6-cylinder engine it took up less space in the engine bay, making it easier to work on. The 5.9L Cummins is constructed of a cast-iron block, cast-iron cylinder heads, and a forged-steel crankshaft. Inside this engine are cast-aluminum pistons and forged-steel rods, designed to withstand high cylinder pressure. Utilizing direct fuel injection and a turbocharger were the key factors in the enhanced performance of the 5.9L Cummins. This engine would be the first 3/4-ton and 1-ton truck to utilize a turbocharger, which was revolutionary for the time. The 5.9L Cummins was fitted with a fixed-geometry Holset H1C Turbocharger, capable of producing up to 18 PSI of boost. Another innovation of this engine was the use of a direct-injection fuel system which injects fuel directly into the combustion chamber. The first 5.9L Cummins powered truck utilized a Bosch VE rotary injection pump that was driven off the camshaft gear. This mechanical pump is designed to increase fuel supply pressure with increasing engine speed and has a maximum pressure of 17,400 PSI in a stock pump. In 1991, Dodge added an intercooler to the 5.9L Cummins to further increase power and efficiency. The intercooler cools the compressed air from the turbo to create denser air to aid in a more efficient combustion process. These revolutionary upgrades gave this engine increased performance, drivability and towing capacity.
The 5.9L Cummins was paired with either an automatic or manual transmission during the 1989-1993 model years. The transmission options offered in these trucks were the Getrag 360 5-Speed Manual, the A727 3-Speed Automatic (offered in 1989-1991), or the A518 (46RH) 4-Speed Automatic Transmission (offered in 1991.5-1993). A stock 5.9L Cummins was rated at 160 hp and 400 lb-ft of torque, which out-ranked the GM 6.2L at 240 lb-ft of torque and the Ford 7.3L IDI at 338 lb-ft of torque. These power levels don’t seem too impressive when compared to new model diesels, but they established the standard for diesel performance. Fortunately, the 5.9L Cummins responds very well to performance modifications to close that power gap. These engines are still highly sought-after for racing, sled pulling events, or other competitions due to their durability and ability to withstand increased power levels. XDP continues to support the 5.9L Cummins with parts from hundreds of the top manufacturers. Check out the wide range of parts and accessories available, including Air Filters, Fuel Injectors, Exhaust Manifolds, Turbo Kits, Suspension Parts and much more! XDP will provide you the parts needed to keep your 1989-1993 Dodge 5.9L Cummins on the road.