281GPFJP-S5AB Chelsea PTO Assembly

The Chelsea 281GPFJP-S5AB or 281GPFJPS5AB is a 281 Series hydraulically shifted hot shift power take-off designed for automatic transmissions with a 10-bolt aperture, including Allison and Caterpillar transmissions. The series carries a continuous torque rating of 390 lb-ft and delivers output options that include SAE B and SAE C pump flanges, ISO 7652 pump flanges, and driveline configurations. The ductile iron bearing cap is 117% stronger than gray iron, and clutch pack steel discs are 80% thicker than the predecessor 280 Series design. Nine speed ratios cover both low- and high-speed applications. The Wet Spline Lubrication option extends shaft life 7 to 10 times compared to standard configurations. A SmartStart feature reduces shock load at engagement, and Electronic Overspeed Control (EOC) protects driven equipment. Call us to confirm proper fit for your transmission and application.

Features

10-Bolt mounting aperture, compatible with Allison and Caterpillar automatic transmissions
Hydraulic PowerShift (hot shift) operation supports continuous-duty use
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 reduces vibrational effects and improves clamp load
Nine speed ratios including low and high speeds; Wet Spline Lubrication option extends shaft life 7 to 10 times
SmartStart reduces engagement shock load; Electronic Overspeed Control (EOC) protects driven equipment

Tech Specs

• Mounting Type: 10-Bolt
• Shift Type: Hydraulic PowerShift (Hot Shift)
• Continuous Torque: 390 lb-ft (529 Nm)
• Continuous Operation: Yes
• Transmission Compatibility: Allison automatic transmissions
• Output Types: SAE B Pump Flange, SAE C Pump Flange, ISO 7652 Pump Flange, Driveline
• Output Shaft Options: SAE B (7/8 in. - 13T) Pump Spline, SAE C (1-1/4 in. - 14T) Pump Spline, 3/4 in. - 11T Pump Spline, SmartStart Round Shaft (1-1/4 in. - 5/16 in. Key), 1410 Companion Flange, DIN 100 Flange, DIN 120 Flange, DIN 5462 Pump Spline
• Speed Ratios: Nine, including low and high speeds
• Lubricant Options: Pressure Lube, Wet Spline
• Shaft Power: 37 HP at 500 RPM, 74 HP at 1000 RPM

Additional Information

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