u/3rkw

Hello, I've been wanting to tune my 2019 X3 M40i to a Stage 2 MHD and xHP. Before doing so, I would like to do some "proper fluid changes" at 60k miles. If I run tuned should I be opting for a thicker oil like 75W-90 for the transfer case and front and rear diff for thermal management or should I stick with OEM like Febi Bilstein? Thanks!

Hello, I've been wanting to tune my 2019 X3 M40i to a Stage 2 MHD and xHP. Before doing so, I would like to do some "proper fluid changes" at 60k miles. If I run tuned should I be opting for a thicker oil like 75W-90 for the transfer case and front and rear diff for thermal management or should I stick with OEM like Febi Bilstein? Thanks!