The Chelsea 281GMFJP-B8RY or 281GMFJPB8RY is a 281 Series hydraulically shifted hot-shift Power Take-Off built for automatic transmissions with a 10-bolt aperture, including Allison transmissions. The 281 Series evolved from the top-selling 280 Series with several structural upgrades: a ductile iron bearing cap rated 117% stronger than gray iron, an O-ring sealing configuration between the housing and bearing cap for improved clamp load, and clutch pack steel discs that are 80% thicker to resist premature tooth wear. Nine speed ratios cover low and high speed demands. Rotatable cast iron flanges reduce interference during pump installation. A genuine Chelsea part from Pro Gear and Transmission. Call us to confirm proper fit for your application.
The Chelsea 281 Series is documented in the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Common markets for this series include fire and rescue, truck cranes, pumper cleaner, and refuse trucks. The Positive Stop feature for driveline outputs eliminates oil seal damage from coupling. Hose is included with this assembly.
Features
Hydraulic hot-shift (PowerShift) operation designed for 10-bolt automatic transmission apertures including Allison transmissions
Ductile iron bearing cap - 117% stronger than gray iron predecessor
O-ring sealing configuration between housing and bearing cap improves clamp load and reduces vibrational effects
Clutch pack steel discs increased 80% in thickness to resist premature tooth wear
Nine speed ratios including low and high speeds
Wet Spline Lubrication option provides 7 to 10 times greater shaft life; SmartStart reduces shock load at start-up; Electronic Overspeed Control (EOC) protects driven equipment
Tech Specs
- Mounting Type: 10-Bolt
- Shift Type: Hydraulic (PowerShift / Hot Shift)
- Compatible Transmissions: Allison automatic transmissions (10-bolt aperture)
- Continuous Torque: 390 lb-ft (529 Nm) - see application pages for actual ratings
- Intermittent Torque: 301 to 400 lb-ft (501+ Nm)
- Output Power: 56+ HP (51+ kW)
- Shaft Power: 37 HP at 500 RPM / 74 HP at 1000 RPM
- Number of Speed Ratios: 9 (including low and high)
- Output Types: SAE B Pump Flange, SAE C Pump Flange, ISO 7652 Pump Flange, Driveline
- Lubricant Options: Pressure Lube, Wet Spline
- Continuous Operation: Yes
Additional Information
The Chelsea 281 Series is documented in the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Common markets for this series include fire and rescue, truck cranes, pumper cleaner, and refuse trucks. The Positive Stop feature for driveline outputs eliminates oil seal damage from coupling. Hose is included with this assembly.
Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
