The Chelsea 890 Series Power Take-Off (PTO), part number 890PBFJW-B5XS or 890PBFJWB5XS, is a hydraulic hot-shift PTO engineered specifically for Allison 3000 MD and 4000 HD Series transmissions. The 890 Series mounts like a standard side-mounted PTO but relocates the pump output flange to the rear of the transmission, creating better clearance between the pump and frame rail. Unlike extension-based designs, the main shaft is a single one-piece unit with no input splines between the PTO body and the output extension. The SAE C output uses Wet Spline Technology to extend pump shaft life under demanding duty cycles. Continuous-duty torque rating reaches 670 ft-lb, with intermittent torque rated at 501+ ft-lb. Output power is 64 HP at 500 RPM and 128 HP at 1,000 RPM. The 10-bolt mounting pattern and an additional rear bracket provide solid transmission support. Common applications include aerial trucks, fire and rescue, refuse, and truck crane work. Call us to confirm proper fit for your specific Allison transmission configuration.
Features
Fits Allison 3000 MD and 4000 HD Series transmissions via 10-bolt mount
Hydraulic PowerShift (hot-shift) engagement
SAE C wet-spline output extends PTO and pump shaft life
Single one-piece main shaft eliminates input splines between PTO body and output
Pump output relocated to rear of transmission for improved pump clearance
Continuous-duty torque rating up to 670 ft-lb; shaft output 64 HP at 500 RPM and 128 HP at 1,000 RPM
Tech Specs
- Transmission Application: Allison 3000 MD and 4000 HD Series
- Product Series: 890
- Mounting Type: 10-Bolt
- Shift Type: Hydraulic PowerShift
- Outlet Flange Type: SAE C
- Output Shaft Type: SAE C (XS) Wet Spline
- Continuous Torque Rating: 670 ft-lb (check application pages for actual torque ratings)
- Intermittent Torque: 501+ ft-lb
- Output Power: 56+ HP (51+ kW)
- Shaft Power: 64 HP (48 kW) at 500 RPM; 128 HP (95 kW) at 1,000 RPM
- Lubricant: Wet Spline
Additional Information
The Chelsea 890 Series is purpose-built for applications where pump clearance and high continuous torque are priorities. It mounts at the side of the Allison 3000 or 4000 Series transmission with a 10-bolt pattern and adds a rear support bracket for stability. The clutch is positioned at the rear of the PTO housing so the gear section tucks tightly against the transmission, maximizing clearance for the pump. Because the main shaft is a single one-piece design, there are no input splines between the PTO and the output extension, removing a common wear point. The SAE C wet-spline output accommodates demanding hydraulic pump applications found on aerial units, fire and rescue trucks, refuse vehicles, and truck cranes. The 890 Series can be configured for transmissions equipped with or without a cooler, a retarder, or both. Part number 890PBFJW-B5XS is sold by Pro Gear and Transmission. Call us to verify the correct configuration for your chassis and pump setup.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
