The John Deere 8870 tractor tire size is front 18.4R38 and the rear is 18.4R42.
Front tire18.4R38
Rear tire18.4R42
Front/rear setupDifferent front and rear tire sizes
Rim diameter38 in front, 42 in rear
Ballast50 gal
John Deere 8870 Tire Size Details
Front tire size
18.4R38
Rear tire size
18.4R42
Front/rear setup
Different front and rear tire sizes
R1 ag tire size
18.4R38, 18.4R34
Front tire construction
Imperial radial
Rear tire construction
Imperial radial
Front section width
18.4 in
Rear section width
18.4 in
Front rim diameter
38 in
Rear rim diameter
42 in
Loaded rear tire ballast / fluid capacity
50 gal
Tire size alternatives / conversions
24.5R32, 18.4R34, 710/70R32, 520/85R34
Tire Size Comparison Chart
Front rim diameter comparison
This model
38 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 8870 Extra Tire Notes
Tire size note
The John Deere 8870 uses different front and rear tire sizes in this data: front 18.4R38 (38 in rim, 18.4 in width) and rear 18.4R42 (42 in rim, 18.4 in width)
Ballast note
For the John Deere 8870 rear 18.4R42 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
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.
