And... he replied. Yes, the "Whale Oil" stuff we want is from toothed whales and is called Spermaceti oil found in the foreheads of sonar using Whales and even Bats. It is a long/tight chain organic hydrocarbon molecule. This not the stuff that was rendered from whale fat and burnt cleanly in lamps. Our stuff is a friction modifier and even a few molecules per square millimeter will keep the clutches slipping smoothly. And by "clutch" we mean all except a Detroit Locker. The others employ spring-loaded friction discs or twin-conical friction cups of dissimilar sintered metals, even the unpopular Gov-Lock. A “clutch” if you will. Similar to the bronze synchro hubs in a trans, the oil keeps them slipping nicely without grabbing. He said there is still 3-5% Whale Oil in the new additive. They get it from Japan that still kills Whales. (nice) He also said he often used 90wt oil with an ounce of ATF in the diffs without problems. Why buy $8 additive when an ounce of left-over ATF will work? So- are there clutches in a Guv-Lock? Yes. Does additive help? Yes.