My Blazer has 119,268 Original miles. 4.3L, Vortec V-6. My A/C Compressor just recently started "throwing" a brown colored powder onto the underside of the hood. By recently, I mean in the last 100 miles or so. The "Techs" at my local Firestone Auto Care Center state it's the Compressor clutch going bad. If that's the case, about how long do I have until the clutch is totally gone? I've found No Oil leaks. There are No unusual noises from Compressor when either A/C or Heater is running. Thanks.