A wierd thing has begun in my truck. When the truck is cold and I use the brakes the first couple of times they are as touchy as one can get, with very little pedal effort. After about 15-20 min around town they need more pedal push and are not as crisp. The rears where set up about 10k ago and the fronts where turned and new pads (raybestos super stops) about 20k ago. Could this be bad fluid ? I am the second owner of the truck and have logged about 40k on it personally. Mostly long dis driving. Any suggestions? (ps "K"s are kilometers, Canadian dude 
