Weak argument, Don M. Intelligent readers will understand what I wrote. My point is he is using something that is not API certified. I did not say he was using it in his engine. I understand they don't license it for transmissions and rear ends. So what? Uncertified anything is still uncertified. And Redline is definitely not an appoved lube for the NV4500 5 speed. They all come with labels and tags warning the user against other than Castrol Syntorq. And Glasmith is doing this because he supports what you've said in other posts.