This thought has crossed my mind a few times and decided to toss it out on this site for your opinions. I see a number of people (on BITOG) switch to M1 products (gear oil, syn. PCMO, etc) and they run it for a short interval but when they do their first drain they are horrified by the darkened color. I've seen a lot of people talk about trying M1 gear oil once and saying it oxidizes fast. Being it was a 'used' system there is some build up of slugde and other material, what if it's just the ester co-base in many of their products doing some cleaning and not really oxidation? I would imagine if this is the case they could ran the oil over a few intervals and it would start to clear up. I haven't seen any UOA's with an oxidation (and TAN) test to prove otherwise. If someone added (here's where I would get slapped around on the other site) ARX in their gearbox or rear end they would expect the oil to come out dirty. I'm just wondering if some people are jumping to conclusions because of what expectations they have. I might switch the gearoil in my truck to M1 and have the local lab run a test on it. It will be awhile but I might go ahead with that.
What are your thoughts on people jumping to conclusions about M1?
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