The Chelsea 281 Series Power Take-Off, part number 281GBFJW-B5RK or 281GBFJWB5RK, is a hydraulically shifted hot-shift PTO designed for automatic transmissions with a 10-bolt aperture, commonly used on Allison transmissions. It 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, and an 80% thicker steel clutch pack to resist premature tooth wear. Nine speed ratios cover both low and high-speed applications. The wet spline lubrication option delivers 7 to 10 times greater shaft life. SmartStart reduces shock load at start-up, and Electronic Overspeed Control (EOC) safeguards driven equipment. Typical markets include fire and rescue, refuse, truck cranes, and pumper-cleaner trucks. Call us to confirm proper fit for your transmission and application.
The 281 Series is an evolution of Chelsea's 280 Series PTO, carrying forward proven design while adding structural and sealing improvements aimed at modern engine vibration profiles. Rotatable cast-iron flanges reduce pump clearance interference issues, and the positive stop on driveline outputs eliminates oil seal damage from coupling contact. A hose is included with the assembly. Applicable Parker Chelsea reference documents include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual.
Features
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
80% thicker steel discs in the clutch pack to resist premature tooth wear
Nine speed ratios, including low and high-speed options
Wet spline lubrication option provides 7 to 10 times greater shaft life
Electronic Overspeed Control (EOC) protects driven equipment; SmartStart reduces shock load at engagement
Tech Specs
- Mounting Type: 10-Bolt
- Shift Type: PowerShift (Hydraulic hot-shift)
- Transmission Compatibility: Allison automatic transmissions (10-bolt aperture)
- Continuous Torque: 390 lb-ft (529 Nm) - verify actual rating on application page
- Output Power: 56+ HP (51+ kW)
- Shaft Power: 37 HP at 500 RPM / 74 HP at 1,000 RPM
- Speed Ratios: Nine (including low and high)
- Lubrication: Wet spline option available
- Output Types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, driveline
- Continuous Operation: Yes
Additional Information
The 281 Series is an evolution of Chelsea's 280 Series PTO, carrying forward proven design while adding structural and sealing improvements aimed at modern engine vibration profiles. Rotatable cast-iron flanges reduce pump clearance interference issues, and the positive stop on driveline outputs eliminates oil seal damage from coupling contact. A hose is included with the assembly. Applicable Parker Chelsea reference documents include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual.
Parts manual and diagrams: Chelsea 281 Series PTO parts list with prices
