Sears GT/18
The Sears GT/18 is a tractor produced by Sears Lawn Tractors. It is equipped with a 781 cc 47.7 ci engine. The listed engine power is Gasoline (gross): 18 hp / 13.4 kW. Transmission: Peerless. Operating weight: 619 lbs 280 kg.
Engine Power
Gasoline (gross): 18 hp / 13.4 kW
Fuel & Capacities
3.25 gal
12.3 L
Transmission
Peerless
Operating Weight
619 lbs
280 kg
Overview
 | 1978 - 1980
Garden tractorRoper built
Garden tractor
Roper built |
|---|
Production | |
|---|---|
Distributor | Sears |
Manufacturer | Roper |
Garden tractor | |
Original price was $2,579 in 1979 | |
Variants | |
|---|---|
GT/18 | gear |
GT18H | hydrostatic |
Sears GT/18 Engine | |
|---|---|
18HP Onan 781cc 2-cyl gasoline | |
Fuel tank | 3.25 gal
12.3 L |
Engine details ...  | |
Sears GT/18 Transmission | |
|---|---|
6-speed gear | |
Transmission details ...  |
Mechanical | |
|---|---|
Two-wheel drive | |
Manual steering | |
Mechanical band brakes | |
Open operator station. |
Power Take-off (PTO) | |
|---|---|
Front PTO | independent |
Clutch | mechanical |
Dimensions & Tires | |
|---|---|
Weight | 619 lbs
280 kg |
Front tire | 16x6.50-8 |
Rear tire | 23x10.00-12 |
Full dimensions and tires ...  | |
Electrical | |
|---|---|
Ground | negative |
Charging system | alternator |
Charging amps | 15 |
Battery volts | 12 |
References | |
|---|---|
 | |
Garden Tractors published in 1980, by Sears | |
Riding Mowers, Lawn Tractors, Garden Tractors and Attachments published in 1979, by Sears | |
Fall/Winter published in 1978, by Sears | |
Spring/Summer Catalog published in 1978, by Sears |
Engine
Engine Detail — 781 cc / 47.7 ci Gasoline
Manufacturer | Onan B48M |
Fuel Type | Gasoline |
Configuration | 2-cylinder, air-cooled horizontal-shaft opposed twin |
Displacement | 781 cc
47.7 ci |
Bore/Stroke | 3.25x2.875 inches
83 x 73 mm |
Power (gross) | 18 hp
13.4 kW |
Starter | electric |
Starter volts | 12 |
Oil capacity | 1.75 qts
1.7 L |
Oil change | 25 h |
Transmission
Transmission — Peerless
Transmission | Peerless |
Type | belt-driven gear |
Gears | 6 forward and 2 reverse |
Clutch | mechanical idler pulley |
Oil capacity | 5 qts
4.7 L |
Oil type | SAE 30 |
Oil change | 480 h |
Dimensions
Sears GT/18 Tires | |
|---|---|
Lawn/turf front | 16x6.50-8 |
Lawn/turf rear | 23x10.00-12 |
Dimensions | |
|---|---|
Length | 68.5 inches
173 cm |
Width | 36.5 inches
92 cm |
Height | 40 inches
101 cm |
Shipping weight | 619 lbs
280 kg |
Attachments
Attachment overview | |
|---|---|
42" mid-mount mower deck | |
48" mid-mount mower deck | |
Snowblower | |
Blade | |
Front-end loader | |
Garden tractors are capable of using tillers, plows, or other ground-engaging attachments. TractorData does not list details of these attachments. |
Photos
Sears GT/18
Sears GT/18
Sears GT/18
Sears GT/18
Recommended Implements & Sizing Guide
Engineering recommendations for Sears Lawn Tractors Sears GT/18 based on its 18 HP power envelope and ASAE agricultural standards.
| Implement & Operation | Recommended Size | Workload Rating | Engineering Notes |
|---|---|---|---|
Moldboard PlowPrimary Tillage | 1 to 2 Bottom (12")1 - 2 铧 (30 cm) | Light Duty | Ideal for garden plots and light sandy soil. |
Rotary Cutter / MowerMowing & Clearing | 4 ft (48 in)1.2 m | Light Duty | Pasture clipping and light brush under 1" diameter. |
Rotary TillerSeedbed Prep | 42 to 48 in105 - 120 cm | Light Duty | Covers compact tractor tire width. |
Sizing & Soil Condition NoteActual implement sizing varies depending on local soil conditions (heavy clay vs sandy loam), field slope, and operating speed. Heavy tillage implements may require front ballast weights and wheel weights.
Fluids, Capacities & Working Autonomy
Standard fluid requirements, service intervals, and continuous runtime estimates for Sears Lawn Tractors Sears GT/18.
Estimated Continuous Field Runtime: 3.5 hrs
Approximately 3.5 hours of continuous field operation at ~75% rated power on a full tank (3.3 gal / 12.3 L).
Estimated 75% Load Fuel Burn~0.9 gal/hr (3.5 L/hr)
Engine Crankcase Oil
SAE 15W-40 (Heavy Duty Diesel)
Standard Spec: API CK-4 / CJ-4 Heavy Duty
Service Interval: 150 – 250 Hours
Transmission & Hydraulic System
UTTO (Universal Tractor Transmission Oil)
Standard Spec: ISO VG 46 / 68 (Wet Brake & Trans Compatible)
Service Interval: 600 – 1000 Hours
Engine Cooling System
50/50 Ethylene Glycol Pre-mix
Standard Spec: ASTM D6210 / Heavy-Duty OAT Antifreeze
Service Interval: 2 Years / 1500 Hours
Sears Lawn Tractors Sears GT/18 Specification Unit Converter
Convert power, fluid capacities, and operating weights between metric and imperial standards for Sears Lawn Tractors Sears GT/18.
Converted Equivalents:
Horsepower (HP)18 hp
Kilowatts (kW)13.4 kW
Metric Horsepower (PS / CV)18.2 PS
Direct Competitor Comparison
Compare Sears GT/18 against same-era industry alternatives in the same horsepower class.
Current Model
Sears Lawn Tractors
Sears GT/18
Engine Power:Gasoline (gross): 18 hp / 13.4 kW
★ Baseline Reference
International HarvesterMarket Competitor
International Harvester Type A 15HP
Engine Power:16.7
Production Years:1908 - 1911
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