ROLLS ROYCE GHOST SERIES II 2 Gearbox 8623148 Gearbox 8-GAN

For the Rolls-Royce Ghost Series II (RR4 Facelift and the newer RR21), the part number 8623148 corresponds to the high-performance ZF 8-Speed Automatic Transmission (8HP90Z).

This gearbox is a cornerstone of the “Magic Carpet Ride,” as it is specifically calibrated to handle the massive torque of the 6.6L and 6.75L V12 engines while remaining nearly imperceptible during shifts.

1. Technical Specifications

• Manufacturer: ZF Friedrichshafen

• Model: 8HP90Z (The “90” denotes its high torque capacity of up to 900 Nm).

• Type: 8-speed Torque Converter Automatic.

• Satellite Aided Transmission (SAT): This gearbox uses GPS data to read the road ahead. If the car “sees” a sharp curve or a hill, it automatically pre-selects the correct gear before you even reach the bend.

• Interchangeable Part Numbers: 24008615281, 24007646098, and 8623148.

2. Vehicle Compatibility

While the part is most common in the Ghost Series II (RR4) produced between 2014 and 2020, it is also found in other V12 applications within the BMW/Rolls-Royce ecosystem:

3. Market Value & Availability (2026)

In 2026, original units with this specific part number are typically sourced as high-quality recycled or refurbished assemblies.

• Used (Pristine Condition)

• Factory Rebuilt

• Service Kit (Fluids/Filter): A genuine ZF LifeGuard 8 service kit (required every 50k–60k miles) retails for approximately

4. Critical Installation Warning

Replacing a Rolls-Royce gearbox is not a “plug-and-play” task. In 2026, these units are heavily integrated into the vehicle’s security and performance software:

• Mechatronics Coding: The internal computer (Mechatronics) is VIN-locked. If you install a used 8623148 gearbox, the car will stay in “Park” unless the software is reset and reflashed using an authorized ISTA/P diagnostic tool.

• The “Lifetime” Myth: Rolls-Royce officially lists the transmission fluid as “Lifetime Fill.” However, specialists in 2026 strongly recommend changing the ZF LifeGuard 8 fluid and the integrated plastic pan filter every 8 years or 60,000 miles to prevent the common “shudder” in lower gears.