RepairPal Certified shops can diagnose and repair your 2004 GMC Sierra 1500. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Cost would depend on locating the leak, evacuating the system and then recharging the system.Cost ill certainly depending on what is found to be wrong.
I was told by a freind that it could be in the dash, if true how long would it take and about the cost.