Just FYI, the OEM BMW fluid and the Castrol are indeed identical in viscosity, 75W140. Next change I will likely go with Redline+FM additive. Although you could probably use the Redline FM additive in the Castrol gear oil, I'll stick with products from the same manufacturer that have been tested together.
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK |
| Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors |
| Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels |
| XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit |