281GMFJP-D5AC Chelsea PTO Assembly

The Chelsea 281 Series Power Take-Off Assembly, part number 281GMFJP-D5AC or 281GMFJPD5AC, is a hydraulically shifted hot-shift PTO engineered for automatic transmissions with a 10-bolt aperture, including Allison applications. The 281 Series is an evolution of the 280 Series, featuring a ductile iron bearing cap rated 117% stronger than gray iron, an o-ring sealing configuration between the housing and bearing cap for improved clamp load, and steel clutch pack discs increased in thickness by 80% to resist premature wear. The series supports continuous operation and is suited for fire and rescue, refuse, pumper/cleaner, and truck crane applications. Call us to confirm proper fit for your specific transmission and application.

Features

Hydraulic PowerShift (hot-shift) operation for engagement under load
10-bolt aperture mounting for Allison automatic transmissions
Ductile iron bearing cap, 117% stronger than gray iron predecessor
O-ring sealing between housing and bearing cap for improved clamp load
Clutch pack steel discs 80% thicker than the prior 280 Series design
Suited for continuous-duty applications including fire and rescue, refuse, and truck crane service

Tech Specs

• Mounting Type: 10-Bolt aperture
• Shift Type: Hydraulic PowerShift (hot-shift)
• Transmission Compatibility: Allison automatic transmissions
• Continuous Operation: Yes
• Continuous Torque (series rated): 390 lb-ft (529 Nm) - verify actual rating on application pages
• Intermittent Torque (series range): 301-400 lb-ft (501+ Nm)
• Output Power (series): 56+ HP (51+ kW)
• Shaft Power: 37 HP at 500 RPM, 74 HP at 1000 RPM

Additional Information

The Chelsea 281 Series PTO is an evolution of the 280 Series platform, with engineering changes focused on reducing damaging vibrational effects associated with modern engine designs. Key improvements over the 280 Series include a ductile iron bearing cap (117% stronger than the previous gray iron cap), an o-ring sealing configuration between the housing and bearing cap, and clutch pack steel discs that are 80% thicker. The series supports nine speed ratios including both low and high speeds. An optional wet spline lubrication configuration provides 7 to 10 times greater shaft life compared to standard lubrication. The Electronic Overspeed Control (EOC) feature protects driven equipment from overspeed events, and the SmartStart option is available to reduce shock load at start-up for select applications. Rotatable cast iron flanges allow improved pump clearance during installation. Parker Chelsea reference documents: 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual.