The Chelsea 890 Series Power Take-Off (part number 890EAFJW-B5AF or 890EAFJWB5AF) is a hydraulic PowerShift PTO engineered specifically for Allison 3000 MD and 4000 HD Series transmissions. It mounts via a 10-bolt pattern and delivers an SAE C ("XS") output flange. The one-piece main shaft eliminates the input splines found between a conventional PTO body and its output extension, placing the clutch at the rear of the housing so the gear section tucks close to the transmission. This geometry moves the pump mounting flange rearward, giving adequate clearance even in tight frame-rail installations. Wet Spline output technology extends pump shaft life under demanding duty cycles. Shaft power reaches 64 HP at 500 RPM and 128 HP at 1,000 RPM, with a continuous torque rating up to 670 ft-lb. Common applications include aerial trucks, fire and rescue units, refuse trucks, and truck cranes. Call us to confirm proper fit for your specific transmission configuration.
Features
Fits Allison 3000 MD and 4000 HD Series transmissions via 10-bolt mount
Hydraulic PowerShift (hot shift) engagement
SAE C ("XS") output shaft and outlet flange
One-piece main shaft with rear-mounted clutch for improved pump clearance
Wet Spline output extends PTO and pump shaft life in demanding conditions
Continuous torque rating up to 670 ft-lb; shaft power 64 HP at 500 RPM, 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
- Output Shaft Type: SAE C ("XS")
- Outlet Flange Type: SAE C
- 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 (48 kW) at 500 RPM; 128 HP (95 kW) at 1,000 RPM
- Lubricant/Output: Wet Spline
- Input Gear Designator: FJ (Allison 3000 MD and 4000 HD Series)
Additional Information
The Chelsea 890 Series is a single-unit PTO - not a PTO body with a bolt-on extension. The one-piece shaft design removes the internal input splines that conventional extended PTOs rely on, reducing potential wear points. The clutch assembly sits at the rear of the housing, allowing the gear section to mount flush against the transmission and freeing space between the transmission and frame rail. This layout suits aerial, fire and rescue, snow and ice, refuse, and crane applications where both pump clearance and high continuous torque are critical requirements. Part number 890EAFJW-B5AF is also referenced as SP890EAFJW-B5AF in some catalog systems. Pro Gear and Transmission carries this genuine Chelsea part - give us a call if you need help confirming the right 890 Series configuration for your truck.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
