Description
The Chelsea 281 Series Power Take-Off, part number 281GCFJP-S5RK or 281GCFJPS5RK, is a hydraulically shifted hot-shift PTO built for automatic transmissions with a 10-bolt aperture, including Allison and Caterpillar units. It is an evolution of the 280 Series, with a ductile iron bearing cap that is 117% stronger than gray iron, an o-ring sealing configuration between the housing and bearing cap to improve clamp load, and an 80% increase in clutch pack disc thickness to resist premature tooth wear. Nine speed ratios cover both low and high ranges. Rotatable cast-iron flanges reduce interference issues with pump mounting. Common markets include fire and rescue, refuse, pumper cleaner, and truck crane applications. A genuine Chelsea part from Pro Gear and Transmission. Call us to confirm proper fit for your application.
Features
Ductile iron bearing cap rated 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 resist premature tooth wear
Nine speed ratios including low and high speeds
Wet spline lubrication option provides 7 to 10 times greater shaft life
Electronic Overspeed Control (EOC) protects driven equipment; SmartStart option reduces shock load at start-up
Tech Specs
- Mounting Type: 10-Bolt
- Shift Type: Hydraulic PowerShift (Hot Shift)
- Compatible Transmissions: Allison and Caterpillar automatic transmissions
- Continuous Torque: 390 lb-ft (529 Nm) – check application pages for actual torque rating
- 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
- Available Output Types: SAE B Pump Flange, SAE C Pump Flange, ISO 7652 Pump Flange, Driveline
- Available Shaft Types: SmartStart Round Shaft (1-1/4″ – 5/16″ Key), 3/4″ 11T Pump Spline, SAE B 7/8″ 13T Pump Spline, SAE C 1-1/4″ 14T Pump Spline, 1410 Companion Flange
- Lubrication: Pressure Lube or Wet Spline options
- Continuous Operation: Yes
- Part Number: 281GCFJP-S5RK or 281GCFJPS5RK
Additional Information
Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.









