D 350 Pickup L6-359 5.9L DSL (1989)
Reduced oil pressure may be an Indication that bearings are wearing. If wear is allowed to continue, bearing clearances become excessive and the
crankshaft will hammer on the bearings, causing a knocking sound.
A rod knock occurs when the engine is not loaded. Verify by first applying load and then unloading and listening for the knock.
