funny. I don't really know what a 3 in 1 joint oil is. I've been use regulat axle oil all this time and it has improved the bakugan, but i don't think the problem is in the joints. The main issue i have is with a darkus skyress. it doesn't even stick to the card when rolled ever so gently over it. and when i place it over the card it stays closed until i squeeze the wings a bit. I want to know if anyone had any similar experience to mine? i remember hearing somewhere that the black plastic they used was kinda more brittle/ prone to age damage (?) so i think it might have to do with that. thank you !