I have a 2002 GMC Sierra 1500HD 4X4 with a 6.0 liter engine. After the vehicle has warmed up (15 - 20 minutes) and I am driving it at 30 - 40 klm/hr and I start to accelerate, a whistle noise will appear until about 80 klm/hr or if I discontinue accelerating. This whistle noise sound like a vacuum leak and is more noticeable while under a load, while pulling a trailer. This noise is not consistent but is very noticeable. The auto mechanics can't seem to figure this one out.
have the same problem?
Friday, June 26th, 2009 AT 2:27 PM