Sources and field evidence
Catalog Archive: Baseline specifications compiled from historical manufacturer archives and equipment registries. Laboratory test report verification in progress.
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Engineering & Capability Benchmark
Specific output, tractive ratio, and segment percentile
Engine and power specifications
- Engine model
- Hercules ZXD
- Fuel type
- Gasoline
- Rated horsepower
- 40 hp
- Rated PTO Power
- 36.82 hp (Gibson specification)
- Drawbar Power @ Rated Engine Speed
- 29.1 hp (Nebraska OECD Test 2218)
- Cylinders
- 6
- Displacement
- 3.9 L (236.7 ci)
- Bore / stroke
- 3.4375x4.125 inches 87 x 105 mm
- Rated RPM
- 1800 RPM
- Crankcase oil capacity
- N/A
- Coolant capacity
- 17 qts (~16.1 L)
Maintenance picks for the I
Filters, oil and common wear parts for this model.
Transmission and chassis specifications
- Transmission type
- Gear (4F/1R)
- Gears (forward / reverse)
- 4 forward / 1 reverse
- Drive system
- 2WD
- Wheelbase
- 94 in
- Front tire
- 5.50-16
- Rear tire
- 10-38
- Hydraulic flow
- N/A
- Rear hitch
- N/A
Implement Draft & Ballast Matcher
Simulate draft resistance, drawbar power transfer, and optimal axle weight distribution for Gibson I.
Engine demand (83.4 HP) exceeds rated power (40 HP). Reduce working speed by 1.0-1.5 mph or reduce working width.
Instant Used Market Valuation Projector
Algorithmic resale estimate for Gibson I (1948)
Direct Segment Rivals & Showdowns
Head-to-head match-ups calibrated by horsepower and era
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Gibson
USA • 8 Models
Gibson was a pioneering American tractor manufacturer with a relatively brief but notable history in the agricultural machinery industry. The company was founded by Wilbur Gibson in Longmont, Colorado, in the early 20th century. Gibson's manufacturing facility in Longmont became the birthplace of several innovative tractor models that gained recognition for their durability and design. The company's early success was marked by its commitment to producing reliable farm equipment that met the needs of American farmers. However, Gibson's independent operation was short-lived, as the company was sold to Helene Curtis Industries in 1952. This acquisition marked a significant turning point for the brand. Following the sale, Western American Industries took over the Gibson factory and resumed tractor production from 1953 to 1958. Despite these efforts, the Gibson brand ultimately ceased operations during this period, and the factory closed permanently. The Gibson legacy is remembered for its contribution to the development of early American tractors and its role in the agricultural machinery landscape of the mid-20th century.
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