Farm Industry News has been releasing the names of the top 40 most fuel-efficient tractors of the decade over the past couple of weeks. Today, the top three, including the "Fuel King," are announced.

Farm Indsutry News compiled the list of the most fuel-efficient tractors with help from the Nebraska Tractor Test Lab. The fuel efficiency ratings are based on the PTO test at rated engine speed. Find the story explaining the rating here.

The second most fuel-efficient tractor of the decade is the John Deere 8320R. Its PTO test at rated engine speed is 18.93, it boasts 274 hp and was tested in 2009.

Tractors 40-30 are listed here.

Tractors 29-20 are listed here.

Tractors 19-10 are listed here.

Tractors 9-1 are listed here.

Special note: Rankings include all high-hp row-crop tractors (150+ hp) tested by the Nebraska Tractor Test Lab in the last 10 years.  Nearly 200 models have been tested during this timeframe, but only the top 40 made the cut for being the best models on fuel. Three of all models tested are equipped with new Tier 4i emissions-compliant engines: Case IH Magnum 340, which ranked 3rd; John Deere 8335R, which ranked 4th, and; the John Deere 8360R IVT, ranking 22nd on the list. More Tier 4i tractors will be tested in 2012, and we will rank them all again at that time.

Also note that rankings are based on the PTO test at rated engine speed, which lab director Roger Hoy says is a good indicator because it is one that is calculated for all tractors and it is always run at the maximum level. (However, he advises tractor buyers to consider the other test measures, too, because power and fuel use will vary depending on the intended application. See tractortestlab.unl.edu <http://tractortestlab.unl.edu/> .)