281GMFJP-B8RF Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off, part number 281GMFJP-B8RF or 281GMFJPB8RF, is a hydraulically shifted hot-shift PTO designed for automatic transmissions with a 10-bolt aperture, including Allison and Caterpillar applications. Built as an evolution of the 280 Series, this unit carries a cross-reference to predecessor part 280GMFJP-B8RF or 280GMFJPB8RF. The 281 Series delivers nine speed ratios covering both low and high ranges, and supports continuous-duty operation. Output options across the series include SAE B and SAE C pump flanges, ISO 7652 pump flanges, and driveline configurations. The enhanced clutch pack features steel discs 80% thicker than the previous design to resist premature tooth wear. Call us to confirm proper fit for your transmission and application.

Features

Hydraulic PowerShift (hot-shift) operation for 10-bolt automatic transmission apertures including Allison and Caterpillar
Ductile iron bearing cap rated 117% stronger than gray iron for greater durability under vibration
Enhanced clutch pack with steel discs 80% thicker than the predecessor 280 Series design
O-ring sealing configuration between housing and bearing cap improves clamp load and reduces vibrational effects
Nine speed ratios including low and high speeds; supports continuous-duty operation
Wet spline lubrication option extends shaft life 7 to 10 times compared to standard lubrication
Electronic Overspeed Control (EOC) protects driven equipment; SmartStart reduces shock load at start-up
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 PowerShift (hot-shift)
• Transmission Compatibility: Allison and Caterpillar automatic transmissions
• Continuous Operation: Yes
• Speed Ratios: Nine, including low and high speeds
• Output Types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, driveline
• Lubrication: Pressure lube or wet spline option
• Cross-Reference: 280GMFJP-B8RF or 280GMFJPB8RF (predecessor part number)

Additional Information

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