The John Deere 1840 tractor tire size is front 7.50-16 and the rear is 15.5-38.
Front tire7.50-16
Rear tire15.5-38
Front/rear setupDifferent front and rear tire sizes
Tire pressure12 PSI, 14 PSI
Rim diameter16 in front, 38 in rear
Ballast30 gal
John Deere 1840 Tire Size Details
Front tire size
7.50-16
Rear tire size
15.5-38
Front/rear setup
Different front and rear tire sizes
R1 ag tire size
7.50-16, 15.5-38, 16.9-30
Front tire construction
Bias/imperial tire
Rear tire construction
Bias/imperial tire
Front section width
7.5 in
Rear section width
15.5 in
Front rim diameter
16 in
Rear rim diameter
38 in
Tire pressure
12 PSI, 14 PSI
Loaded rear tire ballast / fluid capacity
30 gal
Tire Size Comparison Chart
Front rim diameter comparison
This model
16 in
Average
17.1 in
Low
4 in
High
50 in
Rear rim diameter comparison
This model
38 in
Average
25.5 in
Low
0 in
High
50 in
John Deere 1840 Extra Tire Notes
Tire size note
The John Deere 1840 uses different front and rear tire sizes in this data: front 7.50-16 (16 in rim, 7.5 in width) and rear 15.5-38 (38 in rim, 15.5 in width)
Pressure note
For the John Deere 1840 with front 7.50-16 and rear 15.5-38 tires, the pressure values captured in the answer are 12 PSI, 14 PSI. Tire pressure is load-dependent, so use this as a reference value rather than a universal setting
Ballast note
For the John Deere 1840 rear 15.5-38 tires, the ballast figure captured in the answer is 30 gal. Liquid ballast capacity can change by tire brand, fill percentage, wheel setup and ballast fluid type
Front/rear matching note
The John Deere 1840 data shows front 7.50-16 and rear 15.5-38. When changing either size, front/rear rolling circumference and lead/lag need to stay within the correct range
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.
