The John Deere 9R 440 tractor tire size is front 710/70R42 and the rear is 710/70R42.
Front tire710/70R42
Rear tire710/70R42
Front/rear setupSame front and rear tire size
Tire pressure35 PSI, 18 PSI
Rim diameter42 in front/rear
Ballast50 gal
John Deere 9R 440 Tire Size Details
Front tire size
710/70R42
Rear tire size
710/70R42
Front/rear setup
Same front and rear tire size
Tire construction
Metric radial
Section width
710 mm
Aspect ratio
70%
Sidewall height
497 mm
Rim diameter
42 in
Approx overall diameter
about 81.1 in
Tire pressure
35 PSI, 18 PSI
Loaded rear tire ballast / fluid capacity
50 gal
Tire Size Comparison Chart
Front rim diameter comparison
This model
42 in
Average
17.1 in
Low
4 in
High
50 in
Rear rim diameter comparison
This model
42 in
Average
25.5 in
Low
0 in
High
50 in
John Deere 9R 440 Extra Tire Notes
Tire size note
The John Deere 9R 440 uses 710/70R42 on both the front and rear in this data, so the same tire-size details apply to both axles: metric radial, 710 mm section width, 70% aspect ratio, 42 in rim, approx 81.1 in overall diameter
Pressure note
For the John Deere 9R 440 with front 710/70R42 and rear 710/70R42 tires, the pressure values captured in the answer are 35 PSI, 18 PSI. Tire pressure is load-dependent, so use this as a reference value rather than a universal setting
Ballast note
For the John Deere 9R 440 rear 710/70R42 tires, the ballast figure captured in the answer is 50 gal. Liquid ballast capacity can change by tire brand, fill percentage, wheel setup and ballast fluid type
Front/rear matching note
The John Deere 9R 440 data shows the same tire size front and rear (710/70R42). That usually makes the visible front/rear size relationship simpler, but approved tire and wheel combinations should still be checked before mixing brands or changing sizes
Official information note
Mistakes do happen. Tire sizes can change by year, axle, wheel/rim option, tyre brand, tread type and local market. Please check the tire sidewall, operator manual and official deere.com website for official information.
