The Chelsea 281 Series Power Take-Off, part number 281GDFJP-K8RY or 281GDFJPK8RY, is a hydraulically shifted (PowerShift) hot-shift PTO designed for automatic transmissions with a 10-bolt aperture, including Allison transmissions. It carries a single, continuous duty torque rating with nine available speed ratios covering both low and high ranges. The 281 Series builds on the proven 280 Series platform with a ductile iron bearing cap rated 117% stronger than gray iron, an O-ring sealing configuration between the housing and bearing cap to improve clamp load, and clutch pack steel discs that are 80% thicker to resist premature tooth wear. Output options include SAE B and SAE C pump flanges, ISO 7652 pump flange, and driveline configurations. Rotatable cast-iron flanges reduce interference issues, and the Wet Spline Lubrication option extends shaft life 7 to 10 times over standard configurations. SmartStart reduces shock load at start-up, and Electronic Overspeed Control (EOC) protects driven equipment. Common markets include fire and rescue, refuse, truck cranes, and pumper cleaner applications. Call us to confirm proper fit for your transmission and application.
Features
Hydraulic PowerShift (hot-shift) operation for 10-bolt automatic transmissions including Allison
Ductile iron bearing cap, 117% stronger than gray iron, for reduced vibration-related fatigue
Enhanced clutch pack with steel discs 80% thicker than the predecessor 280 Series
O-ring sealing configuration between housing and bearing cap improves clamp load
Nine speed ratios including low and high ranges; Wet Spline Lubrication option extends shaft life 7 to 10 times
SmartStart reduces start-up shock load; Electronic Overspeed Control (EOC) protects driven equipment
Tech Specs
- Shift Type: Hydraulic PowerShift (hot-shift)
- Mounting: 10-bolt aperture
- Compatible Transmissions: Allison automatic transmissions
- Continuous Torque Rating: 390 lb-ft (529 Nm) - verify actual rating on application pages
- 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 1,000 RPM
- Output Types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, driveline
- Output Shaft Options: 1-1/4 in. round with 5/16 in. key (SmartStart), 3/4 in. 11-tooth pump spline, SAE B 7/8 in. 13-tooth pump spline, SAE C 1-1/4 in. 14-tooth pump spline, DIN 5462 pump spline, 1410 companion flange, DIN 120 flange, DIN 100 flange
- Lubrication: Pressure lube or Wet Spline option
- Continuous Operation: Yes
- Reference Documents: 281/288 Series Parts List HY25-2281-M1/US; 267/281/288/871/878 Series Owner's Manual
Additional Information
Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
