2003 GMC GMC TRUCK User Comment / Complaint

Loud clunk in drivetrain when transmission upshifts 2-3 and downshifts 3-2. vehicle is 2003 gmc pick-up truck 4x4. dealer #1 replaced driveshaft. no change. dealer #2 diagnosed the clunk as a momentary torque reversal of the output shaft when the clutch is applied and the 2-4 band released. see gm information bulletin #01-07-30-042c (sept. 27, 2005) gm says this is normal and no repairs should be attempted. this constant clunking is not normal and is aggravating to the driver and owner. a new vehicle should be free of mechanical defect as the warranty states. this condition may be worse in 4x4 vehicles due to tolerances in the transfer case. gm will not rectify this defect while under original warranty. it is their duty to sell a defect free vehicle. i have discussed this problem with gm, bbb, a truck dealer and a transmission repair shop. my conclusion is that a reprogramming of the bands in the transmission case will correct this defect. gm is not willing to make this remedy available to the vehicle. my expectation is that the vehicle should be defect free during warranty period. the standoff! the federal government should protect the unwitting buyer from the failures of auto makers to warrant a defect free product as they claim when they sell the product. otherwise, it is a gross misrepresentation of a promise and fraud.