The Chelsea 890PAFJW-B5AF or 890PAFJWB5AF is a hydraulic PowerShift power take-off built for Allison 3000 MD and 4000 HD Series transmissions. Part of Chelsea's 890 Series, it mounts via a 10-bolt pattern and positions the pump output to the rear of the transmission, providing clearance between the PTO and the frame rail without requiring a separate extension. The main shaft is a one-piece design, eliminating input splines between the PTO body and output. Continuous-duty torque rating reaches 670 lb-ft, with intermittent torque rated at 501+ lb-ft. The SAE C output shaft uses Wet Spline Technology to reduce wear on the PTO and pump shaft under demanding duty cycles. Shaft power output is 64 HP at 500 RPM and 128 HP at 1,000 RPM. Typical applications include aerial trucks, fire and rescue units, refuse trucks, and truck cranes. Available from Pro Gear and Transmission - call us to confirm proper fit for your specific transmission configuration.
Features
Fits Allison 3000 MD and 4000 HD Series transmissions via 10-bolt mounting
Hydraulic PowerShift (hot shift) engagement
SAE C (XS) output with Wet Spline Technology for extended shaft life
670 lb-ft continuous-duty torque rating; 501+ lb-ft intermittent torque rating
64 HP at 500 RPM, 128 HP at 1,000 RPM shaft power output
One-piece main shaft design moves pump flange to rear of transmission for improved pump clearance
Tech Specs
- Transmission Application: Allison 3000 MD and 4000 HD Series
- Product Series: 890
- Mounting Type: 10-Bolt
- Shift Type: Hydraulic PowerShift
- Output Shaft Type: SAE C (XS)
- Lubricant: Wet Spline
- Outlet Flange Type: SAE C
- Continuous Torque Rating: 670 lb-ft (check application pages for actual torque ratings)
- Intermittent Torque: 501+ lb-ft
- Shaft Power: 64 HP at 500 RPM; 128 HP at 1,000 RPM
- Output Power: 56+ HP
Additional Information
The Chelsea 890 Series mounts like a standard side-mounted PTO but adds a support bracket at the rear of the transmission. The clutch is positioned at the rear of the PTO housing, allowing the gear section to sit tightly against the transmission case for tighter packaging. Because the 890 Series is a single-unit design rather than a PTO paired with a bolt-on extension, there are no input splines between the PTO body and the output shaft - a common wear point on conventional setups. The Wet Spline output reduces friction and wear in high-cycle or continuous-duty applications such as aerial lift trucks, pumper/cleaner trucks, fire and rescue apparatus, refuse trucks, and truck cranes. The 890 Series can be ordered for transmissions equipped with or without a cooler, a retarder, or both. Call Pro Gear and Transmission to confirm the correct configuration for your chassis and transmission build.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
