The Chelsea 890 Series Power Take-Off, part number 890HFFJW-B5ZS or 890HFFJWB5ZS, is a hydraulic hot-shift PTO engineered specifically for Allison 3000 MD and 4000 HD Series transmissions. It mounts via a 10-bolt pattern and delivers a continuous-duty torque rating up to 670 ft-lb, with intermittent torque rated at 501+ lb-ft. The SAE C (XS) output shaft uses Wet Spline technology to extend pump shaft life under demanding, high-cycle conditions. Shaft power output is 64 HP at 500 RPM and 128 HP at 1,000 RPM. Unlike a PTO-plus-extension setup, the 890 Series uses a single one-piece main shaft, moving the pump mounting flange to the rear of the transmission for improved clearance between the PTO and frame rail. The clutch sits at the rear of the unit so the housing and gear section tuck tightly against the transmission. Common applications include aerial trucks, fire and rescue, refuse trucks, and truck cranes. Call us to confirm proper fit for your specific Allison configuration.
Features
Fits Allison 3000 MD and 4000 HD Series transmissions via 10-bolt mounting
Hydraulic PowerShift (hot shift) engagement for on-the-fly operation
SAE C (XS) Wet Spline output shaft extends PTO and pump shaft life
Continuous-duty torque rating up to 670 ft-lb; intermittent torque 501+ lb-ft
Single one-piece main shaft eliminates input splines between PTO body and output extension
Pump flange positioned at rear of transmission for improved clearance between unit and frame rail
Tech Specs
- Transmission Application: Allison 3000 MD and 4000 HD Series
- Product Series: 890
- Mounting Type: 10-Bolt
- Shift Type: Hydraulic PowerShift (Hot Shift)
- Outlet Flange Type: SAE C
- Output Shaft Type: SAE C (XS) - Wet Spline
- Continuous Torque: 670 lb-ft (check application pages for actual torque ratings)
- Intermittent Torque: 501+ lb-ft
- Output Power: 56+ HP (51+ kW)
- Shaft Power: 64 HP (500 RPM) / 128 HP (1,000 RPM) | 48 kW (500 RPM) / 95 kW (1,000 RPM)
- Lubricant: Wet Spline
Additional Information
The Chelsea 890 Series is a single-unit design, not a PTO with a bolt-on extension. The one-piece main shaft eliminates the intermediate input splines found on conventional extended-reach setups, which reduces potential failure points in high-torque applications. The clutch is positioned at the rear of the PTO housing, allowing the gear section to sit flush against the transmission and maximize clearance between the unit and the truck frame rail. An additional support bracket at the rear of the transmission is included for rigidity. The 890 Series can be ordered for transmissions equipped with or without a cooler or retarder, or both. Typical applications include aerial work trucks, fire and rescue pumpers, refuse trucks, truck cranes, and snow and ice equipment. Part number 890HFFJW-B5ZS is sold by Pro Gear and Transmission. Call us to confirm fitment for your specific transmission configuration.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
