Just picked the truck, and rebuilt transmission, up this evening. I've never had a dealership ask or care about a tune, on the Ranger or the SHO that I had. If you bring a vehicle in with bald drive tires and a piston sticking through the hood it might be a different story though, haha.I would go ahead and just do it now. I was worried too but after installing it I was so glad I did and not just for the performance but it does shift WAY better. Also now that I think of it @NOVA_Ranger did have an issue with his transmission and even tuned they still covered it. I'll PM you and let you know if I decide to sell it.