I have been getting calls from this number at least twice a day and it started two days after I took my truck to a Chevy dealer for service. I just called 1-800-864-8601 as Jad had suggested on a previous post back on March 4th, 2009 and added my number to their do not call list. I will see if it works and let you all know. Their message did say it could take a couple days before the calls stop.