Comparison Fuel efficiency with the 6.8 liter engine versus the 4.5?

[candersen10]

I am currently looking for a row crop type tractor with between 90 and 110 PTO HP. I have been primarily looking at John Deere equipment but am open to other manufacturers. Has anyone had a chance to compare the fuel usage in John Deere's models with the 6.8 liter engine (such as the 6615 and 6715) versus the 4.5 liter engine (such as the 6030 premium machines)? This tractor will be used primarily for tillage with a 4 bottom rollover plow and disc and also for hay baling/disc mowing. Whenever possible I will use my smaller machines to minimize fuel costs but I want to make sure I don't buy something that is immediately too expensive to own and operate.

 

[BarryinMN]

Those are pretty big horses for here. Another site might get you more responses with daily users = AgTalk Home - Category & forums listing

 

[Charlie175]

John Deere has a handy dandy comparison tool online at

http://fuelsavings.deere.com

Let's you compare engine size and other brands. It is company website though so it might be slewed.

 

[chh]

Here is the link for the Nebraska Test reports. That is the only place I know of that gives unbiased results.
NE Tractor Test Publications

 

[art]

It is so hard to say just by listing an engine size as to the fuel economy. With plowing, how well does the draft control work, what is the weight of the tractor and where does it sit?

I do appreciate the neutrality of the Nebraska tests but I haven't seen to much concrete in a field to use for traction! Can a ag tire really grip he concrete like it's designed to work?

There is a lot of differerence between the field and the track but as stated, it's as good as it might get!

There is no generic cross table to say this size will get this, and that will get that!

 

[Farmwithjunk]

It is so hard to say just by listing an engine size as to the fuel economy. With plowing, how well does the draft control work, what is the weight of the tractor and where does it sit?

I do appreciate the neutrality of the Nebraska tests but I haven't seen to much concrete in a field to use for traction! Can a ag tire really grip he concrete like it's designed to work?

There is a lot of differerence between the field and the track but as stated, it's as good as it might get!

There is no generic cross table to say this size will get this, and that will get that!

That more or less sums up my thoughts on "lab testing".

I've got a 6430 (4.5L) After looking at the fuel consumption specs Deere hands out vs. real world use, I'd have to say Deere is mighty optimistic in their specs. In almost 2 years, we've logged over 2000 hours with a 15' batwing in some mighty tough mowing conditions with fuel use probably 15% to 20% over what we were hoping for, based on Deere sales literature. I'm thinking their test results were in optimal conditions with an eye towards achieving good numbers rather than maximum work output.

Fuel use varies with conditions we're mowing in, and to a degree, even with who's in the operators seat.

Art's comment is spot on. No set rules apply to which one is easiest on fuel based on size of motor alone. It would take a side-by-side comparison in equal conditions to get that sort of info.

 

[Bob_Young]

It may be that tractor weight has more to do with fuel efficiency than engine size. I've noticed that my FWD 43 and 50 HP Kubotas burn but a fraction of the fuel my neighbor's 2WD JDxx40 series tractors (70HP and up). Those things are fuel guzzlers no matter what they're doing. But they are older ('80s?) technology, well broken in, and much heavier, even the 70HP.

If you need the weight, and you probably do for tillage, you may be stuck. If you can get by with a lighter rig, you might save that way.

A lot of existing Ag designs seem to be based on the idea that fuel cost is negligible. As we all know, that's no longer the case. If fuel stays up, I look for Ag thinking to change radically the next few years.
FWIW
Bob

 

[Farmwithjunk]

It may be that tractor weight has more to do with fuel efficiency than engine size. I've noticed that my FWD 43 and 50 HP Kubotas burn but a fraction of the fuel my neighbor's 2WD JDxx40 series tractors (70HP and up). Those things are fuel guzzlers no matter what they're doing. But they are older ('80s?) technology, well broken in, and much heavier, even the 70HP.
Bob

Some of that can be accounted for by the fact that Deere's of that era were plain ol' fuel hogs. I've got a '79 2440 (60hp) In spite of the fact that it's been a great tractor, it can turn a diesel fuel tank inside out faster'n you can say cetane rating. I also owned at one point, a Deere 4250 MFWD, 110 hp. It was an oil company exec's dream come true too. It could flat put away the fuel. Deere's diesel of 1960 to 1990 era were good reliable engines, but no one EVER confused then with EFFICIENT engines. You would need to compare a modern day Deere with your Kubotas. Deere has got a little better. And, MFWD does make a significant difference in drawbar pulling efficiency.