I just got done with my 4/6 drop and after driving the truck about 5 or 6 miles the ABS light came on and Service Brake System warning cam eup on the dashboard. What things should I be looking for? Up front I disconnected the wheel speed sensors when changing the lower control arms, but reconnected them when I put everything back together. In the rear I don't remember seeing any wires. The rear must just use the VSS right? I also changed from 3.23 gears and 31.6 tall tires to 4.10 gears and 29" tall tires and have not yet recalibrated the speedo.