megan post # 102
Dexron III has been in use on CHC S76 series helicopters for over 30 years, most common brand we use today is Mobil 1 ATF . see from the C++ manual on approved oils for the main gear box ( applies the same to intermediate and tail).
I have been with the S76 in very cold climates and very hot I have never experienced any problems using this oil. In this many years of operating many S76īs all over the world I think is long enough to say it works just fine and the gearboxes normally make TBO and no defects are being reported by the overhaul or repair shops due to using this oil.
My only complaint is the smell of the oil is quite strong.
Lubricating oil, DODPRF-85734 (preferred)
MIL-L-23699,
MIL-L-21260,
Type I, Grade
30, or
Dexron III, ATF