The Chelsea 890 Series Power Take-Off, part number 890HAFJW-G5AZ or 890HAFJWG5AZ, is a hydraulic PowerShift PTO engineered specifically for Allison 3000 MD and 4000 HD Series transmissions. It mounts via a 10-bolt pattern and positions the SAE C pump output flange at the rear of the transmission, gaining clearance between the PTO and the frame rail without requiring a separate extension. The main shaft is a single one-piece design that eliminates input splines between the PTO and output extension. Continuous-duty torque rating reaches 670 lb-ft, with intermittent torque rated at 501+ lb-ft. The wet-spline output extends pump and PTO shaft life under demanding duty cycles. Shaft power delivers 64 HP at 500 RPM and 128 HP at 1000 RPM. Common applications include aerial trucks, fire and rescue, refuse trucks, and truck cranes. 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 mounting
Hydraulic PowerShift (hot-shift) engagement
SAE C (XS) output shaft with wet-spline technology for extended pump and shaft life
Continuous-duty torque rating up to 670 lb-ft; intermittent torque 501+ lb-ft
One-piece main shaft eliminates input splines between PTO and output extension
Shaft power: 64 HP at 500 RPM, 128 HP at 1000 RPM
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)
- Outlet Flange Type: SAE C
- Lubricant: 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 (1000 RPM) / 48 kW (500 RPM), 95 kW (1000 RPM)
Additional Information
The Chelsea 890 Series is a single-unit PTO, not a PTO with a bolt-on extension. The clutch is located at the rear of the unit so the housing and gear section sit tightly against the transmission, improving pump clearance over conventional side-mount configurations. An additional bracket at the rear of the transmission provides support alongside the standard side-mount interface. The 890 Series accommodates Allison transmissions equipped with or without a cooler, a retarder, or both. Typical service platforms include aerial trucks, fire and rescue pumpers, refuse trucks, and truck cranes where high torque output and limited pump bay space are priorities.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
