281GMFJP-H5AC Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off, part number 281GMFJP-H5AC or 281GMFJPH5AC, is a hydraulically shifted hot-shift PTO built for automatic transmissions with a 10-bolt aperture, commonly matched to Allison transmissions. It is an evolution of the Chelsea 280 Series, carrying over several structural upgrades: the bearing cap is ductile iron, rated 117% stronger than gray iron, and the clutch pack uses steel discs 80% thicker than the previous design to resist premature tooth wear. An o-ring sealing configuration between the housing and bearing cap improves clamp load and reduces vibration-related wear. The assembly covers nine speed ratios, including low and high speeds, and supports continuous-duty operation. Rotatable cast-iron flanges help reduce pump interference clearance issues. Available with a Wet Spline Lubrication option that delivers 7 to 10 times greater shaft life. SmartStart reduces shock load at engagement, and the Electronic Overspeed Control (EOC) protects driven equipment. Call us to confirm the right configuration for your application.

Features

Hydraulic hot-shift (PowerShift) operation for use with 10-bolt automatic transmission apertures, commonly Allison
Ductile iron bearing cap, 117% stronger than gray iron predecessor
Clutch pack steel discs increased 80% in thickness to resist premature tooth wear
O-ring sealing configuration between housing and bearing cap reduces vibration effects and improves clamp load
Nine speed ratios available, spanning low and high speed ranges
Wet Spline Lubrication option extends shaft life 7 to 10 times compared to standard
SmartStart feature reduces shock load at engagement; 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 aperture
• Shift Type: Hydraulic hot-shift (PowerShift)
• Transmission Compatibility: Allison automatic transmissions
• Continuous Operation: Yes
• Speed Ratios: Nine, including low and high speeds
• Bearing Cap Material: Ductile iron (117% stronger than gray iron)
• Lubrication Option: Wet Spline (W) or Pressure Lube (P)
• Output Types: SAE B Pump Flange, SAE C Pump Flange, ISO 7652 Pump Flange, Driveline
• Electronic Overspeed Control (EOC): Included
• SmartStart: Available for applicable configurations

Additional Information

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