The Chelsea 890MDFJW-B5XK or 890MDFJWB5XK is a hydraulic hot-shift power take-off from the Chelsea 890 Series, purpose-built for Allison 3000 MD and 4000 HD Series transmissions. The 10-bolt mounting configuration locates the SAE C output flange at the rear of the transmission, moving the pump further back to clear tight frame-rail spaces. A one-piece main shaft eliminates the input splines found on conventional PTO-plus-extension designs. Wet-spline output technology reduces wear on the PTO and pump shaft in demanding duty cycles. Continuous-duty torque rating for this series reaches 670 lb-ft, with shaft power of 64 HP at 500 RPM and 128 HP at 1,000 RPM. Common applications include aerial trucks, fire and rescue vehicles, refuse trucks, and truck cranes. A genuine Chelsea part available from Pro Gear and Transmission. Call us to confirm proper fit for your application.
Features
Fits Allison 3000 MD and 4000 HD Series transmissions via 10-bolt mounting
Hydraulic PowerShift (hot-shift) operation
SAE C ("XS") output shaft and outlet flange
One-piece main shaft eliminates input splines between PTO and output extension
Wet-spline output extends PTO and pump shaft life in demanding conditions
Extended shaft positions the pump to the rear of the transmission for improved clearance
Tech Specs
- Transmission Application: Allison 3000 MD Series 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") Output
- 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 (48 kW) at 500 RPM; 128 HP (95 kW) at 1,000 RPM
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 for tighter clearance. The unit is a single assembly, not a PTO combined with a separate extension, which simplifies installation and reduces potential leak points. Typical markets include aerial, fire and rescue, refuse, on-highway, and defense applications. The 890 Series can be ordered for transmissions fitted with or without a cooler, a retarder, or both. Part number 890MDFJW-B5XK is also referenced as SP890MDFJW-B5XK.Parts Manual: Chelsea 890 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
