BMW 4 series Gran Coupé, G26 (USA)
Automatic transmission fluid capacity & service interval
BMW 4 series Gran Coupé, G26 (USA) uses automatic transmission fluid with a capacity range of 8 to 9,28 liters. The data covers 6 configurations.
The configuration chart below lists fill volumes and service intervals for each engine and trim variant.
| Type | Specifications |
|---|---|
| 430i Gran Coupé (2024- ) |
|
| 430i xDrive Gran Coupé (2024- ) |
|
| M440i Mild-Hybrid Gran Coupé (2022-2024) |
|
| 430i Gran Coupé (2021-2024) |
|
| 430i xDrive Gran Coupé (2021-2024) |
|
| M440i Mild-Hybrid xDrive Gran Coupé (2021-2024) |
|
Additional Notes
- The BMW 4 Series Gran Coupé G26 automatic transmission fluid capacities fall into two distinct values across the lineup: 9.28 liters and 8 liters. The 9.28-liter figure is the higher of the two and is associated with a full transmission service fill, accounting for fluid retained in the torque converter and valve body during a drain-and-fill procedure.
- The 430i Gran Coupé carries a 9.28-liter automatic transmission fluid capacity for the 2021-2024 model years. Starting from 2024, the capacity for the same model is listed at 8 liters, indicating a revised transmission unit or updated service procedure adopted at that point.
- The 430i xDrive Gran Coupé follows the same capacity pattern as the rear-wheel-drive 430i variant. The 2021-2024 specification lists 9.28 liters, while the 2024 entry lists 8 liters, suggesting the capacity revision applies across both drivetrain configurations of the 430i.
- The M440i Mild-Hybrid Gran Coupé, covering the 2022-2024 model years, carries a 9.28-liter automatic transmission fluid capacity. The mild-hybrid system in the M440i integrates a 48-volt belt-alternator-starter but does not alter the transmission fluid capacity relative to the non-hybrid 430i of the same period.
- The M440i Mild-Hybrid xDrive Gran Coupé, spanning 2021-2024, also specifies 9.28 liters of automatic transmission fluid. The addition of xDrive all-wheel drive does not produce a different transmission fluid capacity compared to the rear-wheel-drive M440i Mild-Hybrid variant.
- All six configurations listed carry a normal use condition designation, meaning the specified capacities apply to standard operating environments rather than severe-duty cycles such as frequent towing, extreme temperatures, or high-performance track use.
- The 1.28-liter difference between the 9.28-liter and 8-liter capacity figures is a meaningful distinction in transmission service. A lower service fill capacity can reflect a revised sump design, a different fluid pan, or a recalibrated fill procedure rather than a fundamentally different transmission family.