The last year Ford produced the 7.3-liter eight-cylinder turbo diesel in the E-series vans was 2003. The fluid and other specifications for the 7.3-liter turbo diesel remained the same during the years Ford manufactured the engine. You should always consult your owner's manual to verify fluid levels and monitor the various dip sticks to ensure your vehicle is not over-filled.
Almost all diesels, including the 7.3-liter turbo, require SAE 15w40 engine oil. Ford recommends a synthetic or synthetic blend oil. Special oil additives constructed for diesel engines like Lucas Heavy Duty Oil Stabilizer help to enhance performance while reconditioning the engine seals within a diesel engine. Use of an oil stabilizer with the turbo diesel will prolong the life of the engine.
The 7.3-liter requires 15.1 quarts of oil added with an oil change. Always check the oil after an oil change to verify it's full. Most Ford dipsticks read about halfway up the marks on the dipstick when full. Use a WIX 51734 oil filter or other manufacturer's equivalent when changing the oil. High-flow and extended-use filters will benefit the older models of this engine.
Transmissions on the 7.3-liter call for synthetic multi-vehicle automatic transmission fluid (ATF). The transfer case uses the same oil. Standard front and rear differentials need SAE 80w90 gear oil, whereas the limited slip differentials require SAE 75w140. Use ATF fluid for the power steering and DOT-3 brake fluid in the brake and clutch reservoirs.
