The Ford 7.3 Power Stroke is a light truck version of the International T444E. There are some things between the two that are different, many of them are cost related issues to keep the price of the engine down for Ford customers. The waterpump is one example.
The cooling system on the 7.3 Power Stroke is way over kill. Additionally, the ECM does not use the coolant temperature in making adjustments to fuel timing, ratios, etc. All of that is done by using oil temperatures.
When the 7.3 Power Stroke was introduced in 1994.5 through somewhere in '95/'96, Ford used and inventoried thermostats that were 203 degrees, the same that International used in the T444E. The EPA intervened and found that the light duty Ford motor produced too many NO2 emissions. Ford replaced its inventory with a 195 degree thermostat. They are not interchangeable between the T444E, which is a medium duty application, and the 7.3 Power Stroke because of the difference in the water pumps. There are some places that are making 203 degree thermostats for 7.3's. It raises the oil temperature, and I found that doing that improved my FE about a 1/2 to 3/4 MPG. Additionally, throttle response was better, and the engine was smoother in the 1800 to 2000 RPM's when the 7.3's kind of drone a bit.
More information here...
http://www.dieselsite.com/index.asp?...ROD&ProdID=186
30MPG? I think you'd have to work hard to get it. Generally, often, the problem with a diesel is that it has so much umph, they get to be too fun to drive; it's a rush.
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