281GMFJP-G5XV Chelsea PTO Assembly

The Chelsea 281GMFJP-G5XV or 281GMFJPG5XV is a 281 Series hydraulically shifted, hot-shift power take-off built for automatic transmissions with a 10-bolt aperture, including Allison and Caterpillar units. The 281 Series is an evolution of the 280 Series, with a ductile iron bearing cap rated 117% stronger than gray iron, an 80% thicker clutch pack steel disc for reduced tooth wear, and an O-ring sealing configuration between the housing and bearing cap to improve clamp load and resist vibrational stress from modern engine designs. Nine speed ratios cover both low and high-speed applications. Rotatable cast-iron flanges reduce interference fit issues at the pump mounting face. The series delivers 56+ HP of output power. Call us to confirm proper fit for your specific transmission and application.

Features

Hydraulic PowerShift (hot-shift) operation for engagement under load on 10-bolt automatic transmissions
Ductile iron bearing cap, 117% stronger than gray iron predecessor
80% thicker steel discs in the clutch pack 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, spanning low and high-speed ranges
Wet Spline Lubrication option extends shaft life 7 to 10 times compared to standard lubrication
SmartStart feature reduces shock load at start-up; Electronic Overspeed Control (EOC) protects driven equipment

Tech Specs

• Mounting Type: 10-Bolt aperture
• Shift Type: Hydraulic PowerShift (hot-shift)
• Continuous Operation: Yes
• Series Continuous Torque Rating: 390 lb-ft (529 Nm) - verify actual rating on application pages
• Output Power: 56+ HP (51+ kW)
• Shaft Power: 37 HP at 500 RPM / 74 HP at 1000 RPM (28 kW at 500 RPM / 55 kW at 1000 RPM)
• Transmission Compatibility: Allison automatic transmissions (10-bolt aperture)
• Output Types: SAE B Pump Flange, SAE C Pump Flange, ISO 7652 Pump Flange, Driveline
• Output Shaft Options: 3/4"-11T Pump Spline, SAE B 7/8"-13T Pump Spline, SAE C 1-1/4"-14T Pump Spline, 1410 Companion Flange, SmartStart Round Shaft 1-1/4" with 5/16" key
• Speed Ratios: Nine ratios including low and high speeds
• Lubrication: Pressure Lube or Wet Spline options
• Related Documents: 281/288 Series Parts List HY25-2281-M1/US; 267/281/288/871/878 Series Owner's Manual; Chelsea PTO Stud Kits HY25-2002-M1_US

Additional Information

The Chelsea 281 Series is suited for demanding vocational markets including fire and rescue, truck cranes, pumper cleaner units, and refuse vehicles. The positive stop design on driveline outputs eliminates oil seal damage from coupling contact. The included hose ships with the unit, eliminating a separate order step. Electronic Overspeed Control (EOC) is available to protect driven equipment from overspeed events, and the SmartStart feature is available for applications requiring reduced shock load at engagement.

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