Cummins 6BT 5.9 parts

The 6BT 5.9 is the most numerous Cummins engine in the world, and the regional stock of small standby sets, agricultural plant, light trucks and pumps reflects that. Under a generator it typically covers the 60 to 150 kVA range. Its ubiquity makes parts cheap and available; it also makes the 6BT the family where the widest range of quality circulates under the same part number.

The 306 numbers on this page cover the 6BT 5.9 in genset and industrial duty. Because the engine appears in so many applications, the description field matters more than usual here — a water pump for a genset-configured 6BT and one for a vehicle installation can carry different numbers despite the same engine designation, and the difference is in the mounting and the pulley rather than anything you would notice in a catalogue listing.

On this family the tier decision is genuinely open. There is excellent branded aftermarket for most 6BT service parts — filters, water pumps, gasket sets, starters — made by manufacturers who supply the original equipment. There is also a large volume of unbranded product that is not excellent. Our position is the same as everywhere else on this site: we will offer you the Tier 2 option openly when it is a brand we would fit, we will price it against the genuine part on the same quotation, and we will never sell you aftermarket described as genuine.

For a quotation we need the engine serial number and, ideally, the CPL. Tell us the application — genset, vehicle, pump, agricultural — because on this family the application changes the number more often than the engine does.