I am new to this forum and would appreciate it if you can help me.
I drive E39 M52tub20 and the engine is burning oil. I am planning to replace it, However I am not sure if I should get M52tub20, M52tub25, M54b25 or M54b22.
The fuel is very expensive where I live. The car does around 170 KM/ 20 Liter without the AC and without any aggressive acceleration. The car has a manual gearbox and will change the gearbox as well.
Many thanks for your time in reading my post and your response is much appreciated.