I saw some royal purple gear oil at the store the other day and was wondering if anyone has every used it or what they think about it.

Gear oil, or more specifically hypoid GL-5 spec oil is an entirely different product than oil designed for a motorcycle clutch/transmission. They may both be called gear oil and may even have a similar weight rating, but will not work the same.

Only mention it because I'm guessing the royal purple is gl-5 hypoid gear oil.

I've seen their tanker trucks and I can only assume you mean their 40wt tranny oil. I think its another advertising gimmick like scamsoil.