Engine Performance problem
2002 GMC Sierra V8 Four Wheel Drive Automatic
About a year ago, I was getting about 21 mpg, now I can't get more than 13 mpg. I have changed the spark-plugs which didn't change anything. I purchased the truck new and has no other major problems that I can tell. No warning lights. I do get an occassional cluck, I believe it's the u-joints on the drive shaft. Where should I start to look.
have the same problem?
Sunday, January 17th, 2010 AT 8:36 AM