The Chelsea 899KDFJW-M5XS or 899KDFJWM5XS is a constant mesh power take-off from the Chelsea 899 Series, designed specifically for Allison 4700 Series transmissions. The 899 Series mounts via a 10-bolt pattern and positions the pump mounting flange at the rear of the transmission, creating improved clearance between the PTO and the frame rail. The output shaft is an SAE C 1-1/4"-14T pump spline with wet spline technology to extend PTO and pump shaft service life in demanding duty cycles. Series intermittent torque rating exceeds 501 lb-ft, with continuous-duty torque up to 670 lb-ft depending on application. Typical applications include aerial trucks, fire and rescue vehicles, truck cranes, and refuse trucks. Call us to confirm proper fit for your specific transmission configuration.
Features
Constant mesh (non-shiftable) design for Allison 4700 Series transmissions
10-bolt mounting pattern with rear-positioned pump flange for improved frame rail clearance
SAE C 1-1/4"-14T wet spline output shaft extends PTO and pump shaft life
Series intermittent torque rating: 501+ lb-ft; continuous-duty up to 670 lb-ft
Suited for aerial, fire and rescue, refuse, and truck crane applications
One-piece main shaft eliminates input splines between PTO body and output extension
Tech Specs
- Mounting Type: 10-Bolt
- Shift Type: Constant Mesh
- Outlet Flange Type: SAE C
- Output Shaft Type: SAE C 1-1/4"-14T Pump Spline
- Output Spline Lubrication: Wet Spline
- Series Intermittent Torque: 501+ lb-ft (501+ Nm)
- Series Output Power: 56+ HP (51+ kW)
- Transmission Application: Allison 4700 Series
Additional Information
The Chelsea 899 Series was developed to address clearance limitations on the Allison 4700 platform. Unlike a standard side-mounted PTO with a bolt-on extension, the 899 Series uses a single one-piece main shaft, which removes the input splines between the PTO housing and the output section. The pump interface sits at the rear of the transmission, allowing the housing and gear section to tuck tightly against the transmission for tighter packaging. An additional bracket at the rear of the transmission provides supplemental support. The 899 Series can be configured for transmissions equipped with a cooler, a retarder, both, or neither. The NMFC classification for this assembly is 128520 (Hydraulic PTOs, Pumps, Motors, etc.).Parts Manual: Chelsea 899 Series PTO Parts Manual (PDF) — exploded views, item numbers and the full parts breakdown for this series.
