281GMGJP-B5SD Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off, part number 281GMGJP-B5SD or 281GMGJPB5SD, is a hydraulically shifted hot-shift PTO engineered for automatic transmissions with a 10-bolt aperture, commonly Allison and Caterpillar units. It carries a single continuous-duty torque rating up to 390 lb-ft (529 Nm) at the series level, with nine available speed ratios covering both low and high ranges. The ductile iron bearing cap is 117% stronger than gray iron, and the o-ring sealing configuration between the housing and bearing cap improves clamp load while reducing the vibrational effects of modern engine designs. The clutch pack features steel discs that are 80% thicker than the predecessor 280 Series design to resist premature tooth wear. Wet Spline Lubrication option extends shaft life 7 to 10 times compared to standard configurations. Electronic Overspeed Control (EOC) is included to protect driven equipment, and SmartStart reduces shock load at start-up. Rotatable cast-iron flanges reduce interference fit issues, and a positive stop on driveline outputs eliminates oil seal damage from coupling. A genuine Chelsea part from Pro Gear and Transmission. Call us to confirm proper fit for your application.

Features

Hydraulic PowerShift (hot-shift) operation for 10-bolt automatic transmission apertures, commonly Allison and Caterpillar
Ductile iron bearing cap rated 117% stronger than gray iron predecessor
O-ring sealing configuration between housing and bearing cap improves clamp load and resists vibrational damage
Clutch pack steel discs are 80% thicker than the 280 Series for reduced premature tooth wear
Nine speed ratios available including low and high ranges
Electronic Overspeed Control (EOC) protects driven equipment; SmartStart reduces start-up shock load
Wet Spline Lubrication option provides 7 to 10 times greater shaft life
Rotatable cast-iron flanges reduce pump clearance interference; positive stop on driveline outputs prevents oil seal damage

Tech Specs

• Mounting Type: 10-Bolt aperture
• Shift Type: Hydraulic PowerShift (hot-shift)
• Continuous Torque (series): 390 lb-ft (529 Nm)
• Speed Ratios: Nine, including low and high
• Continuous Operation: Yes
• Compatible Transmission Manufacturers: Allison, Caterpillar
• Output Types: SAE B pump flange, SAE C pump flange, ISO 7652 pump flange, driveline
• Lubrication: Pressure lube (P) or Wet Spline (W) options

Additional Information

The 281 Series is an evolution of the Chelsea 280 Series PTO, engineered for fire and rescue apparatus, truck cranes, pumper cleaners, and refuse vehicles. Applicable Parker Chelsea documents for this series include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Part number 281GMGJP-B5SD is also referenced as SP281GMGJP-B5SD. Not sure this is the right PTO for your transmission? Give us a call.

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