WHILE ATTEMPTING TO COME TO A STOP ON A HIGHWAY EXIT RAMP, WHEN I APPLIED FIRM PRESSURE TO THE BRAKE ABOUT HALF WAY DOWN THE RAMP, THE ENGINE ACCELERATED UNEXPECTEDLY AND THE REAR WHEELS ON MY TRUCK BEGAN TO SPIN AND SLIP. ALTHOUGH THE TRUCK WAS SLOWING DOWN IT COULD NOT COME TO A COMPLETE STOP AND STRUCK A STOPPED VEHICLE AT THE END OF THE RAMP AT SLOW SPEED. WITH EXTREME PRESSURE ON THE BRAKE THE TRUCK REMAINED STOPPED BUT THE REAR WHEELS CONTINUED TO SPIN AT A HIGH RATE. I SHIFTED TO NEUTRAL AND TURNED OFF THE IGNITION KEY. THE TRUCK IS AN AUTOMATIC AND WAS IN 2 WHEEL DRIVE AND THE AUTO SPEED CONTROL WAS NOT ON. I CHECKED THE FLOOR MATS BECAUSE I HAD PREVIOUSLY RECEIVED A SAFETY RECALL INTERIM NOTICE AND HAD PREVIOUSLY MADE SURE THE MATS WERE CORRECTLY INSTALLED. THE ALL WEATHER FLOOR MAT WAS CORRECTLY INSTALLED AND SECURED TO THE 2 FLOOR HOOKS, AND WAS NOT ON THE ACCELERATOR PEDAL. WHEN THE IGNITION WAS TURNED BACK ON THE TRUCK OPERATED NORMALLY AND HAS CONTINUED TO DO SO, NOW ABOUT 2 WEEKS. *TR