281GBFJP-G5RF Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off, part number 281GBFJP-G5RF or 281GBFJPG5RF, is a hydraulically shifted hot-shift PTO engineered for automatic transmissions with a 10-bolt aperture, commonly used on Allison transmissions. This unit delivers a single, continuous duty torque rating and offers nine speed ratios covering both low and high ranges. The ductile iron bearing cap is 117% stronger than gray iron, and an O-ring sealing configuration between the housing and bearing cap improves clamp load while reducing the effects of engine vibration. The clutch pack features steel discs 80% thicker than the previous generation to resist premature tooth wear. Rotatable cast-iron flanges reduce interference fit issues, and the Positive Stop feature for driveline outputs eliminates oil seal damage from coupling. A Wet Spline Lubrication option provides 7 to 10 times greater shaft life, and Electronic Overspeed Control (EOC) protects driven equipment. SmartStart reduces shock load at start-up for applicable configurations. A genuine Chelsea part from Pro Gear and Transmission. Call us to confirm proper fit for your application.

Features

Ductile Iron Bearing Cap - 117% stronger than gray iron for increased durability
O-ring sealing configuration between housing and bearing cap to improve clamp load and reduce vibrational effects
Enhanced Clutch Pack - steel discs 80% thicker than previous generation to resist premature tooth wear
Nine speed ratios including low and high ranges
Rotatable cast-iron flanges reduce interference and improve pump clearance
Wet Spline Lubrication option provides 7 to 10 times greater shaft life
Positive Stop for driveline outputs eliminates oil seal damage from coupling
SmartStart reduces shock load at start-up for certain applications
Electronic Overspeed Control (EOC) protects driven equipment

Tech Specs

• Mounting Type: 10-Bolt
• Shift Type: PowerShift (Hydraulic)
• Transmission Compatibility: Allison automatic transmissions (10-bolt aperture)
• Continuous Torque Rating: 390 lb-ft (529 Nm) - see application pages for actual rating
• Intermittent Torque: 301 to 400 lb-ft
• 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 speeds)
• Lubricant Options: Pressure Lube (P) or Wet Spline (W)
• 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 the Chelsea 280 Series PTO, introduced with structural and sealing upgrades to address the demands of modern engine designs. Typical markets include fire and rescue, truck cranes, pumper cleaners, and refuse vehicles. The hose required for hydraulic shifting is included with the unit. For application-specific torque ratings, consult the Chelsea 281 Series application pages or reference Parker documents: 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual.

Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.