One problem related to brake disc pads has been reported for the 2001 GMC Sierra. The most recently reported issues are listed below.
Disc rotor delamination, anti-lock control. I was pulling a 3/4 ton van stuck in his yard, as I got him close to the hard surface ( driveway) I put on the brakes and the truck wouldn't stop, it hit the corner of his block house. No damage to the house however I had to replace all but hood and one headlight assy. 10 mph and neither bag deployed. I thought it was my own stupidity until reading all the issues on here w/ gm's braking problems. I feel a bit better about myself. The big issue !! all four rotors delaminated w/ 46,000 miles this is the 1st new truck I've owned and believe me it's been babied for sure. I was told by my service dealer there was nothing gm would do about this problem it was my problem for not driving it as much as I should (b. S. ) dealer wanted to charge me a grand to replace all the rotors and pads I did it for 500. 00 and still have the old parts. I'm sure gm should issue a recall on this, it is a definite safety issue did I fail to mention the muffler had a rattle in it and was replaced within the 1st 1000 miles, the thump in the steering column that has no way to be lubricated. Man I am disappointed in gm products.