what gear oil

[BasscatCougar2022]

i Have a 2024 Mercury 300R with a torque master lower unit on a bass boat. motor model number 13000141A serial number 3B418330. i read one place to use High performance 90 Gear oil then in another place to use Mercury Racing Extreme 85W-90 gear oil. so Don which one

[EuropeanAM]

Mercury recommends their Racing/Extreme gear oil. It does seem to hold up well in the racing cases.

HP can be used- recommend it be changed about every 25 hours though. An interesting note: the HP (High Performance) lube was actually the RACING lube until about 6 years ago.