The Chelsea 281 Series Power Take-Off, part number 281GGFJW-N5RY, is a hydraulically shifted hot-shift PTO designed for automatic transmissions with a 10-bolt aperture, including Allison transmissions. The 281 Series carries a continuous torque rating of 390 lb-ft and is rated for continuous operation. Output options across the series include SAE B and SAE C pump flanges, ISO 7652 pump flange, and driveline configurations. The 281 Series is an evolution of the 280 Series, featuring a ductile iron bearing cap that is 117% stronger than the gray iron predecessor, an o-ring sealing configuration between the housing and bearing cap, and an 80% increase in clutch pack steel disc thickness for extended service life. Common markets include fire and rescue, refuse, truck cranes, and pumper cleaner applications.
Features
Hydraulic PowerShift (hot-shift) operation for engagement under load
10-bolt mounting aperture, compatible with Allison automatic transmissions
390 lb-ft continuous torque rating; rated for continuous-duty operation
Ductile iron bearing cap, 117% stronger than gray iron predecessor
O-ring seal between housing and bearing cap for improved clamp load
80% thicker steel discs in the clutch pack to resist premature wear
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
- Shaft Power: 37 HP at 500 RPM / 74 HP at 1000 RPM
- Speed Ratios: Nine ratios available (low and high speeds)
- Lubrication: Pressure lube and wet spline options
Additional Information
The 281 Series is the direct evolution of the Chelsea 280 Series PTO, engineered to address vibrational loads produced by modern engine designs. Key structural upgrades include a ductile iron bearing cap, an o-ring sealing interface between the housing and bearing cap, and an 80% increase in clutch pack steel disc thickness. The series also supports SmartStart to reduce shock load at engagement, and Electronic Overspeed Control (EOC) to protect driven equipment. Wet spline lubrication is available and is reported to provide 7 to 10 times greater shaft life compared to standard lubrication. Applicable markets include fire and rescue, refuse, truck cranes, and pumper cleaner operations. Chelsea documents covering this series include the 281/288 Series Parts List (HY25-2281-M1/US) and the 267/281/288/871/878 Series Owner's Manual. Pro Gear and Transmission carries this genuine Chelsea part.Parts Manual: Chelsea 281 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
