Dayco PB1771N Engine Harmonic Balancer

Dayco Premium OEM Replacement Balancer for BMW V12

The Dayco PB1771N is a premium OEM replacement engine harmonic balancer built for select BMW V12 applications. It is engineered with a neutral balance design, a steel outer ring, and dual integrated serpentine pulleys to support accessory drive operation on the 2003-2008 BMW 760Li and 2004-2006 BMW 760i.

Key Features

• Brand: Dayco Premium OEM Replacement Balancer
• Part number: PB1771N
• Engine harmonic balancer with neutral, no-counterweight balance
• Steel outer ring construction
• Two integrated pulleys with serpentine profiles
• 4-groove pulley and 6-groove pulley arrangement
• 8 bolt holes for mounting
• Crank bore: 1.497 in. / 38.00 mm
• Overall outside diameter: 7.087 in. / 180.00 mm
• Overall width: 2.441 in. / 62.00 mm

Detailed Description

Dayco PB1771N is a direct-fit style harmonic balancer for BMW 760Li and BMW 760i models listed in the fitment data. As part of Dayco’s Premium OEM Replacement Balancer line, it is built for applications that require accurate crankshaft damping and proper accessory drive alignment. The dual integrated serpentine pulleys, one 4-groove and one 6-groove, support the belt routing used on these vehicles, while the steel outer ring and neutral balance design match the needs of the engine platform.

This part number, PB1771N, is intended for 2003-2008 BMW 760Li and 2004-2006 BMW 760i applications. It does not include timing marks, a crank trigger/exciter plate, hardware, or installation instructions.

What It Is Used For

• Replacing a worn or damaged BMW harmonic balancer
• Restoring crankshaft vibration damping
• Correcting belt drive alignment issues
• Addressing pulley wobble or accessory drive noise
• Supporting proper serpentine belt operation on BMW 760Li and BMW 760i engines

Installation Notes and Tips

Verify crank bore, bolt hole quantity, pulley groove count, and overall dimensions before installation. Because hardware is not included, reuse or source the correct fasteners separately as required by the vehicle. Confirm belt routing and pulley alignment during installation, and inspect the crankshaft snout and surrounding components for wear before fitting the balancer.

Quality Assurance

Dayco’s Premium OEM Replacement Balancer line is positioned for OE-style replacement applications, and PB1771N is built to match the listed BMW fitment and dimensional specifications. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.