The Chelsea 281 Series Power Take-Off, part number 281GDFJP-B5SB or 281GDFJPB5SB, is a hydraulically shifted, hot-shift PTO engineered for automatic transmissions with a 10-bolt aperture, including Allison transmissions. The 281 Series is an evolution of Chelsea's 280 Series, featuring a ductile iron bearing cap rated 117% stronger than gray iron and an O-ring sealing configuration between the housing and bearing cap to improve clamp load and reduce vibration-related wear. The clutch pack uses steel discs that are 80% thicker than the predecessor design. Nine speed ratios cover both low and high-speed applications. Rotatable cast-iron flanges improve pump clearance, and the wet spline lubrication option extends shaft life by 7 to 10 times. Electronic Overspeed Control (EOC) and SmartStart are available to protect driven equipment and reduce start-up shock. Call us to confirm proper fit for your transmission and application.
The Chelsea 281 Series is suited for demanding markets including fire and rescue, truck cranes, pumper cleaners, and refuse vehicles. The series supports continuous-duty operation and is compatible with multiple output configurations. Parker Chelsea reference documents for this series include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Part number 281GDFJP-B5SB is also referenced as SP281GDFJP-B5SB. Not sure this is your part? Give us a call.
Features
Ductile iron bearing cap, 117% stronger than gray iron predecessor
O-ring sealing configuration between housing and bearing cap reduces vibration effects and improves clamp load
Enhanced clutch pack with steel discs 80% thicker than the prior 280 Series design
Nine speed ratios, including low and high-speed selections
Wet spline lubrication option provides 7 to 10 times greater shaft life
Electronic Overspeed Control (EOC) and SmartStart reduce driven-equipment damage and start-up shock load
Tech Specs
- Mounting Type: 10-Bolt
- Shift Type: PowerShift (Hydraulic), hot-shift
- Compatible Transmission Manufacturer: Allison
- Speed Ratios: Nine (includes low and high speeds)
- Continuous Operation: Yes
- Continuous Torque: 390 lb-ft (529 Nm) - verify actual rating on application pages
- Intermittent Torque: 301-400 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: SmartStart Round Shaft (1-1/4" with 5/16" key), 3/4"-11T Pump Spline, SAE B (7/8"-13T), SAE C (1-1/4"-14T), DIN 5462 Pump Spline, 1410 Companion Flange, DIN 120 Flange, DIN 100 Flange
- Lubrication: Pressure Lube or Wet Spline
- Series: Chelsea 281 Series (evolution of 280 Series)
Additional Information
The Chelsea 281 Series is suited for demanding markets including fire and rescue, truck cranes, pumper cleaners, and refuse vehicles. The series supports continuous-duty operation and is compatible with multiple output configurations. Parker Chelsea reference documents for this series include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Part number 281GDFJP-B5SB is also referenced as SP281GDFJP-B5SB. Not sure this is your part? Give us a call.
Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
