CUMMINS-4BT-6BT-BEARING-CRANKSHAFT-THRUST-050

3945665 is a crankshaft thrust bearing for Cummins 4BT and 6BT engines, in the 050 oversize. This bearing controls crankshaft end-float — the small amount of fore-aft movement the crank is allowed inside the block — and as it wears that end-float increases, which shows up as clutch engagement feeling different or, on more worn examples, a noticeable clunk when the drivetrain changes load direction. The 050 size is specified where the thrust surfaces have previously been machined oversize. Orange.net.za ships this part fast across South Africa.