FIRST PROBLEM OCCURRED JAN 97 WHILE DRIVING IN RENO NEVADA IT BEGAN TO SNOW LIGHTLY AND FOUR WHEEL DRIVE WAS ENGAGED BUT THIS DRIVER COULD NOT FEEL OR SENSE A CHANGE IN TRACTION. THE BRAKING SYSTEM DID NOT ADJUST TO CHANGING WEATHER CONDITIONS AND WE EVENTUALLY SKIDDED OFF THE ROAD AS CONDITIONS WORSENED AND ANOTHER VEHICLE REAR ENDED ME. I SUFFERED RIGHT ROTATOR CUFF TEAR AND HAD A DISC REMOVED FROM MY NECK. MY PASSANGER HAS HAD TWO BACK SURGERIES DUE TO DISC INJURIES. ON AT LEAST TWO OTHER OCASIONS THE BRAKES NEARLY CAUSED ME TO REAR END SOMEONE BECAUSE OF A SLOW RESPONCE.