The Chelsea 281GMFJP-B3RY or 281GMFJPB3RY is a hydraulically shifted (PowerShift) Power Take-Off from the Chelsea 281 Series, designed for automatic transmissions with a 10-bolt aperture, including Allison and Caterpillar applications. The 281 Series is an evolution of the 280 Series, carrying a continuous torque rating of 390 lb-ft (529 Nm) and nine available speed ratios spanning low and high ranges. A ductile iron bearing cap, 117% stronger than gray iron, and an upgraded clutch pack with 80% thicker steel discs address the vibrational loads common in modern engine designs. Rotatable cast iron flanges reduce pump clearance conflicts, and a Wet Spline Lubrication option extends shaft life 7 to 10 times. Electronic Overspeed Control (EOC) and the SmartStart feature protect downstream equipment at engagement. Call us to confirm proper fit for your transmission and application.
The Chelsea 281 Series builds on the proven 280 Series platform with targeted upgrades for fire and rescue, truck crane, pumper/cleaner, and refuse applications. The hose is included with the assembly. For questions about output shaft configuration or fitment to a specific transmission model, contact Pro Gear and Transmission directly.
Features
10-Bolt mounting aperture for Allison and Caterpillar automatic transmissions
Hydraulic PowerShift (hot shift) operation for continuous-duty use
390 lb-ft (529 Nm) continuous torque rating across nine speed ratios including low and high
Ductile iron bearing cap rated 117% stronger than gray iron predecessor
Enhanced clutch pack with 80% thicker steel discs to resist premature tooth wear
Electronic Overspeed Control (EOC) and SmartStart reduce shock load and protect driven equipment
Tech Specs
- Mounting: 10-Bolt aperture (Allison and Caterpillar automatic transmissions)
- Shift Type: PowerShift (Hydraulic hot shift)
- Continuous Torque: 390 lb-ft (529 Nm)
- Speed Ratios: Nine ratios, including low and high speeds
- Output Types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, driveline
- Lubricant System: Pressure lube (P) or Wet Spline (W) option
- Output Power: 56+ HP (51+ kW)
- Shaft Power: 37 HP at 500 RPM / 74 HP at 1,000 RPM
Additional Information
The Chelsea 281 Series builds on the proven 280 Series platform with targeted upgrades for fire and rescue, truck crane, pumper/cleaner, and refuse applications. The hose is included with the assembly. For questions about output shaft configuration or fitment to a specific transmission model, contact Pro Gear and Transmission directly.
Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
