Hello everyone.
We have Lancer Evo 8 rally edition (not Ralliart, own made), previous owner was used Muller oil in gearbox (Samsonas dogbox), transfer case and differential. But when I diassembled gearbox and transter case, at first sight, the oil was not there at all - it's mullers oil viscisity. In my opinion, it's very bad, because we are not have oil film on gearwheel. On previous sport cars (with static limited slip differential) we used Redline Heavy Shockproof (75W250) and don't have anything problems (with temparature or other). Muller is have 75W140 viscosity.
Main question - can I use Redline Heavy Shockproof with 75W250 viscosity in t-case and differential (Detroit made) without fear?
Motul and other oils, please, do not offer, because in my region I can't find original.
Thanks!