9 material differences · fewer than 12
Tractor oneFord 6401954–1957No measured PTO figureTractor twoJohn Deere 8201967–1975No measured PTO figure
Which should you choose?
Read our verdict on the 640 and the 820 → It is generated from the rows below by a fixed, versioned rule set, and names the figure behind every call.
Field by field
9 material differences · 2 fields identical or within 5%, which is not counted as material
| Field | 640 | 820 | Gap |
|---|---|---|---|
| Engine | |||
| Engine power, claimed claimed | 31.9 hp | 31.5 hp | — |
| Engine declared | — | John Deere M 4 3 L 9 or 3.152 DL-01 | — |
| Displacement declared | — | 2.47 L | — |
| Transmission | |||
| Top speed declared | 12.4 mph · 20 km/h | 12.4–15.5 mph · 20–25 km/h | differs |
| Clutch declared | — | Pedal operated dry Fichtel & Sachs single disc clutch | — |
| Hydraulics & hitch | |||
| Pump flow declared | 2.7–6.0 gpm · 10.2–22.7 L/min | 6.9 gpm · 26.0 L/min | differs |
| Pressure declared | — | 1,944 psi · 134 bar | — |
| Rear PTO speeds declared | 540 rpm | 540/1000 rpm | differs |
| Weight & dimensions | |||
| Unladen weight declared | 3,018 lb · 1,369 kg | 4,740 lb · 2,150 kg | +57% 820 |
| Maximum permissible mass declared | — | 7,716 lb · 3,500 kg | — |
| Wheelbase declared | 74.5 in · 1,892 mm | 74.4 in · 1,890 mm | — |
| Length declared | 120.8 in · 3,069 mm | 134.8 in · 3,425 mm | +12% 820 |
| Width declared | 63.9–87.5 in · 1,623–2,223 mm | 59.1–85.0 in · 1,500–2,160 mm | differs |
| Ground clearance declared | 21.0 in · 533 mm | 15.7 in · 400 mm | +33% 640 |
| Turning radius, braked declared | 18.0 ft · 5.49 m | 9.2 ft · 2.80 m | +96% 640 |
| Fuel tank declared | 52.8 qt · 50.0 L | 66.0 qt · 62.5 L | +25% 820 |
Height is not in this table. It is not one measurement: the sources measure it to different points — over the cab on some machines, over the steering wheel or the exhaust on others — and the same tractor measured two ways can differ by most of a metre. It appears here only when both machines' figures carry the point they were measured to and it is the same point, which is not the case for these two. Each machine's own page prints its height as its source gives it.
Ford 640 sources
Source
- Source: Traktorenlexikon, “Ford 600”
John Deere 820 sources
Source
- Source: Traktorenlexikon, “John Deere 820”