As A-C goes, if you can swing a 8000 series tractor vs the 7000, you'll be much happier. 8050 or 8070 vs the 7050 or 7060 as an example. They are pretty much identical tractors, but the newer 8000 series has a MUCH better cab. Better layout of the dash and controls, and MUCH easier to get in and out of. Better visibility. Better lighting. If you need front wheel assist, it wasn't available on the 7000 series tractors. More room to put your lunch box.
Been so long since I've run my uncles 7020 (black belly), 7060 (maroon belly) or 8070, I can't give much help on fuel consumption. As I recall, they seemed to be pretty good on fuel. Still smokey, though.
The 426 engine is a pretty nice one, but doesn't have quite as much torque as a comparably sized Deere of the same vintage. He has had the engined turned up a bit as well. Around 225hp now, IIRC.
For fuel efficiency, the Nebraska Tractor tests go by hp hours per gallon (the engine hp divided by the number of gallons burnt per hr.).
So, as an example- 200hp tractor burnt 15 gal/hr.= 13.33 hp hrs/gal.
Using that, the 8070 (426CID engine) did 170.72hp and 15.97 hp hrs/gal on the PTO= 10.69 gal/hr.
The 8010 (301 CID engine) did 107.38hp and 14.79= 7.26 gal/hr.
There is a difference of 3.43 gal/hr, but how much more work was done in the same amount of time? The 8070 also made a bit more power per gal (1.18 more hp hrs /gal), so on a per hp comparison, the 8070 is more fuel efficient.
I use gal/acre doing tillage work. We used to have a Deere 8300 w/ MFWD and a Deere 9100 4wd tractors. Pulling the same implements (faster with the 91), the 91 usually used about .25- .5 gal/ac LESS than the 83. The 9100 was rated at 280hp, and the 83 at 200hp.
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'93 W350 CC, LE, 5spd, HTT modded H1C, 4" DE
Sold- '99 3500 Q/C, SO CTD, 4x4, 5spd.
Traded off- '97 3500 C/C, 4x4, CTD
'92 W250, LE, CC, CTD w/ tweaked pump
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