The Chelsea 852XBAKP-B4XU or 852XBAKPB4XU is an 852 Series Hydraulic PowerShift Power Take-Off assembly designed for Allison automatic transmissions with 8-bolt PTO mounting apertures. The 852 Series features a cast iron housing and heavy-duty ball bearings on the output shaft, supporting an intermittent torque rating up to 500 lb-ft (678 Nm - check application pages for actual torque ratings). The output shaft is a 1-1/2"-10T spline with a 1410 companion flange. Shaft power output reaches 95 HP at 1,000 RPM and 48 HP at 500 RPM. Three internal speed ratios are available within the 852 Series. Pressure lubrication is standard. Common applications include oil field service, bulk transporter trucks, and fire and rescue vehicles. Call us to confirm proper fit for your specific Allison transmission and truck configuration.

• Transmission Manufacturer: Allison
• Mounting Type: 8-Bolt
• Shift Type: Hydraulic PowerShift
• Output Shaft Type: 1-1/2" - 10T Spline with 1410 Companion Flange
• Intermittent Torque: Up to 500 lb-ft / 678 Nm (Check Application Pages for Actual Torque Ratings)
• Output Power: 56+ HP / 51+ kW
• Shaft Power: 48 HP (500 RPM) / 95 HP (1,000 RPM) | 36 kW (500 RPM) / 71 kW (1,000 RPM)
• Lubrication: Pressure Lube Standard
• Continuous Operation: Yes, with 30% de-rating

The Chelsea 852 Series is suited for demanding vocational markets including oil and gas, mobile, and municipal equipment. Typical applications include oil field service rigs, bulk transporter trucks, and fire and rescue apparatus. Three internal speed ratios are available across the 852 Series, giving specifiers flexibility when matching the PTO to pump or driveline requirements. The 852 Series is also covered by Parker Chelsea documentation including the 272/282/852/885 Series Owner's Manual and the 852 Series Parts List (HY25-2852-M1_US). Not sure this is the right PTO for your transmission? Give us a call and we can help confirm the correct fit.