The John Deere 9R 490 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
Rim diameter42 in front/rear
Ballast50 gal
John Deere 9R 490 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
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 490 Extra Tire Notes
Tire size note
The John Deere 9R 490 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
Ballast note
For the John Deere 9R 490 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 490 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.
