2003 Chevy Trailblazer 6 cyl Two Wheel Drive Automatic 87000 miles
I recently have experienced problems with my front brakes dragging. Took it in for repair and ended up replacing both front calipers, pads and turndown rotors. First day or so everything fine, however now am experiencing several issues. After vehicle has sat for awhile (ie overnight or all day at work) first five minutes of driving no problems. However after about 5 minutes I start to notice drag on the vehicle, brake pedal is extremely touchy and hard feeling (no problem braking/stopping) and the transmission shift is slow. When I accelerate it feels like I am towing something and when I take foot off of gas pedal, vehicle immediately slows down like in a lower gear. When accelerating typically RPM raise to between 2500-3000 before shifting and once reach desired speed over drive kicks in and then RPM usually sit around 1500-1800. When this situation occurs, RPM rises to almost 3500 before shifting, doesn't feel like it shifts to overdrive and RPM rides about 2000-2200.
Sometimes I can come to a complete stop and put the vehicle in park and depress brake pedal all the way down and then put it back in drive and it seems to get better. Other times these symptoms go away on their own and work normal. I have tested the brake booster by pumping brake 3-4 times with vehicle off and pedal gets very hard. With foot on pedal, I start vehicle and pedal drops slightly. I do have ABS but have gotten no warnings illuminated at any time.
Any suggestions as to what is the cause?