2016, truck. GDE tune installed at about 32 k. Now the truck has 44K on it. Cooler level has only dropped about a quarter of an inch. I run Amsoil 10-40 Synthetic oil, I drive it like a sports car, 85-90 on the interstate sometimes. My only regret is that I did not leave my ECU stock and buy a tuned ECU from GDE. Now I am afraid to take my truck in to get the new recall update preformed on my truck. If the dealer flashes my ECM my tune will be loss and I have no way to get it back. So I plan to keep my oil changed and drive my truck until it DIES.Chances of the cooler leaking after the tune are rare, however the cooler can start to leak at anytime.. I am at 92k miles and tuned for last 60k miles. Original cooler still.