The Australian ag publication, Farm Weekly, is reporting that John Deere has fired a shotgun at the tractor industry after it announced recent official Nebraska tractor test results relating to its 8335R row crop tractor.

Aiming at no competitor in general, the company pulled the trigger in a myth-busting exercise it hopes will vindicate its decision to continue with cooled exhaust gas recirculation (EGR) engines to meet strict environmental laws by 2014.

Farmers already are being bombarded with information on new tractor engines and how they relate in terms of power and fuel efficiency.

"Myths that John Deere's single fluid, cooled exhaust gas recirculation (EGR) and exhaust filter approach to IT4 (Interim Tier 4 exhaust emissions standards) would come with large sacrifices in efficiency were officially busted with the release of official Nebraska OECD results," a special company release to its world-wide dealer network said.

"Compared to competitive IT4 engines that require a second fluid, urea, which is often sold for more than $US6 a gallon ($A5.70 a litre) and can be consumed at rates around seven per cent of diesel use, John Deere's diesel-only approach results in lower operating costs while placing less burden on the operator."

Currently, Deere is the only major tractor manufacturer sticking with EGR.

AGCO already has installed Selective Catalytic Reduction (SCR) engines in its latest Fendts and Massey Ferguson models and Case IH, New Holland, Challenger and PFG (Versatile) will follow suit (Caterpillar and Cummins engines are SCR-designed).

Deere said its 8335R was the first Interim Tier 4 tractor to have undergone Nebraska OECD testing and the results, it says, delivered record-breaking power while maintaining excellent fuel efficiency.

"The 8335R is the first row-crop tractor to break through the 300 power take-off (PTO) hp (224Kw) barrier, delivering 306.6 PTO hp (229Kw) in the rated engine speed PTO test," the release said.

"The 8335R is the most powerful row-crop tractor ever tested at Nebraska.

"This is a record it should not keep for long, though, because John Deere offers an even larger model yet, the 8360R, which is also undergoing official Nebraska OECD testing.

"The record-breaking power of the Year 2011 8R Series proves once and for all that IT4 emission-compliance does not mean less power.

"Power is not the only area the 8335R excelled.

"The tractor delivered record-breaking power while maintaining excellent fuel efficiency and delivered better fuel efficiency than the 8320R it replaced in the 75 per cent of pull at maximum power drawbar test - the test often referred to as the test that most closely represents typical tractor field work.

"The 8335R underwent 23 hours of testing across the various conditions required in an official Nebraska OECD test and did not initiate a single active filter cleaning.

"Although the tractor did not have to perform an active filter cleaning throughout the test procedures, it is noted in the official Nebraska Test report that active exhaust filter cleanings consume an average of only 0.04 gph (0.18L/hr) across total tractor use, or less than one per cent of the total fuel consumed.

Official Nebraska OECD tests can be found on the NlTL website at: