2005 GMC YUKON XL 1500 Electronic Stability Control Esc Problems

MY 2005 YUKON XL WILL, AT RANDOM, SHIFT ITSELF INTO 4 WHEEL LO. IT HAPPENS WHILE DRIVING AND AT SPEEDS OF 30+ MPH. ALL OF THE LIGHTS ON THE PUSH-BUTTON 4WD CONTROL MODULE WILL LIGHT UP OR FLASH. NO AMOUNT OF BUTTON-PUSHING WILL DISENGAGE 4 WHEEL DRIVE. I THE CAR WILL SLAM TO A 5 MPH CRAWL WHEN IT DOES THIS. ALSO THE TRACTION CONTROL SYSTEM DEACTIVATES AT THE SAME TIME. HAS HAPPENED OVER 40 TIMES NOW.

THE VEHICLE'S HYDRAULIC BRAKE LINES HAVE RAPIDLY CORRODED, TO THE POINT THAT THEY MAY GIVE OUT ANY DAY. THE VEHICLE HAS BEEN WELL-MAINTAINED (ALL SERVICE PERFORMED BY A GM DEALER) AND HAS RECEIVED REGULAR UNDERCARRIAGE WASHING. IN ADDITION, THE ELECTRONIC BRAKE CONTROL MODULE (EBCM) HAS JUST FAILED; IF A BRAKE FLUID LEAK OCCURS, THERE WILL BE NO WARNING OR INDICATION PRESENTED BY THE VEHICLE AND THE VEHICLE MAY NOT BE ABLE TO STOP. GM HAS STATED THAT ANY REPAIRS FOR THESE SERIOUS SAFETY HAZARD CONDITIONS WOULD NEED TO BE PAID OUT OF POCKET, WITH AN APPROXIMATE COST OF $2500. A VEHICLE THAT IS LESS THAN 10 YEARS OLD SHOULD NOT SUCH EXHIBIT CORROSION TO THE POINT OF A SAFETY HAZARD. *JS

A FRIEND OF MINE JUST SHOWED ME A LETTER HE GOT IN THE MAIL THAT IS A RECALL TO FIX THE REDUCED ENGINE POWER CODE THAT SHOWS A THROTTLE BODY NEEDS REPAIRED.. THE LETTER SAYS TO BRING HIS VEHICLE IN IF IT IS A GM OR CHEVY MODEL LESS THAN 10 YEARS OLD AND LESS THAN 150000 MILES AND THEY WILL FIX IT FOR FREE. I CONTACTED GM TO SEE IF MY GMC WAS ON THE LIST AND THEY TOLD ME TO TAKE IT TO A DEALER AND HAVE A DIAGNOSTIC DONE. I HAVE ALREADY HAD ONE DONE AND THE CODES KEEP CHANGING, AND FROM WHAT I HAVE READ THE GM SITE AND OTHER FORUMS GM DOES NOT KNOW WHAT THE PROBLEM AND WILL NOT RECALL IT UNLESS THEY HAVE TO, MY BROTHER IS ALSO A MECHANIC AND HAD IT LOOKED OVER BY OUR COLLEGE MECHANIC SHOP.STILL NO RELIEF, I...

DURING ACCELERATION AND OCCASIONALLY DURING BRAKING, THE WHEEL SENSOR(S) CAUSE THE TRACTION CONTROL TO BECOME ACTIVE, OR CAUSE THE ANTI-LOCK BRAKES TO ENGAGE. IN ALL CASES, ACTIVATION IS IN ERROR BASED ON AMBIENT CONDITIONS. I AM ABLE TO OVERRIDE THE TRACTION ACTIVE PROBLEMS BY DISABLING THE TRACTION ASSIST, BUT THE ANTI-LOCK BRAKES ARE NOT CONTROLLED BY THE SAME SWITCH. I HAVE SEARCHED THE INTERNET AND FOUND NUMEROUS EXAMPLES OF THE SAME FAILURE WITH THIS TYPE OF VEHICLE, BUT NO RECALL EXISTS YET FOR THIS PARTICULAR YEAR AND MODEL. TO DATE, THE FAILURE HAS NOT CAUSED A CRASH, BUT NOW THAT WINTER IS HERE I HAVE TO MAKE REPAIRS BECAUSE DISENGAGING THE TRACTION ASSIST IS NOT PRACTICAL IN SNOWY CONDITIONS. MY MECHANIC ADVISED ME THAT IT REQUIRES CHANGING THE FULL FRONT WHEEL BEARING ASSEMBLY BECAUSE OF CORROSION BUILDUP ON THE TONE RING. HE ALSO TOLD ME THAT HE DID CHANGE A...