My son's 1996 F250 has the 351W (5.8) and about 140K miles. It runs great - good power, no smoke, starts easy but it is burning a huge amount of oil. About 1 quart for every 100-200 miles. If you only checked the oil when you filled it up it would be almost 2 quarts low. Could the oil ring be letting this much oil by while the compression rings are still doing their job?
When we bought this truck the thermostat was sticking and had probably gotten the engine very hot with the previous owner. We flushed the system and installed a new thermostat and everything is fine now. A mechanic told us that getting an engine hot could cause the cylinder walls to glaze and contribute to oil burning - at the time we didn't know it was burning this much oil. Currently running 5W40 Rotella T6.
When we bought this truck the thermostat was sticking and had probably gotten the engine very hot with the previous owner. We flushed the system and installed a new thermostat and everything is fine now. A mechanic told us that getting an engine hot could cause the cylinder walls to glaze and contribute to oil burning - at the time we didn't know it was burning this much oil. Currently running 5W40 Rotella T6.