281GSFJP-B8RK Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off, part number 281GSFJP-B8RK or 281GSFJPB8RK, is a hydraulically shifted hot-shift PTO engineered for automatic transmissions with a 10-bolt aperture, commonly used on Allison transmissions. The 281 Series is an evolution of the 280 Series and adds a ductile iron bearing cap rated 117% stronger than gray iron, an O-ring sealing configuration between the housing and bearing cap for improved clamp load, and an enhanced clutch pack with 80% thicker steel discs to resist premature tooth wear. Nine speed ratios cover both low- and high-speed applications. Rotatable cast-iron flanges reduce interference fit issues, and a Positive Stop for driveline outputs eliminates oil seal damage from coupling. Cross-references: 280GSFJP-B8RK or 280GSFJPB8RK. Call us to confirm proper fit for your application.

Features

Hydraulic (PowerShift) hot-shift operation for 10-bolt automatic transmissions including Allison
Ductile iron bearing cap - 117% stronger than gray iron predecessor
Enhanced clutch pack with 80% thicker steel discs to resist premature tooth wear
O-ring sealing configuration between housing and bearing cap improves clamp load and reduces vibrational effects
Nine speed ratios available, covering low- and high-speed needs
Wet Spline Lubrication option provides 7 to 10 times greater shaft life
SmartStart reduces shock load at start-up; Electronic Overspeed Control (EOC) protects driven equipment
Rotatable cast-iron flanges reduce pump clearance interference; Positive Stop for driveline outputs eliminates oil seal damage

Tech Specs

• Mounting Type: 10-Bolt
• Shift Type: Hydraulic (PowerShift) Hot-Shift
• Transmission Compatibility: Allison automatic transmissions (10-bolt aperture)
• Continuous Operation: Yes
• Series Continuous Torque Rating: 390 lb-ft (529 Nm) - check application pages for actual torque rating
• Series Intermittent Torque: 301 to 400 lb-ft (501+ Nm)
• Series Output Power: 56+ HP (51+ kW)
• Shaft Power: 37 HP at 500 RPM / 74 HP at 1000 RPM
• Speed Ratios: Nine, including low and high
• Lubrication: Pressure Lube or Wet Spline options
• Cross Reference: 280GSFJP-B8RK or 280GSFJPB8RK

Additional Information

The Chelsea 281 Series replaces and improves upon the 280 Series platform. Typical market applications for the 281 Series include fire and rescue apparatus, truck cranes, pumper cleaners, and refuse vehicles. The series supports multiple output types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, and driveline outputs. Output shaft options within the series include Smart Start round shaft (1-1/4 in. with 5/16 in. key), 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, and DIN 100 flange. Relevant Parker Chelsea documentation includes the 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.