From: crwlr@verizon.net   
      
   "Mike"  wrote in message   
   news:38Kwj.4944$Sa1.1389@news02.roc.ny...   
   >   
   > "Jeff Strickland"  wrote in message   
   > news:jXIwj.33484$T8.17184@trnddc03...   
   >> It needs a ballast resistor.   
   >   
   >  It doesn't use one.   
   >   
   >   
      
   Ballast resistor is the functioinal equivelent to the blower resistor.   
      
      
   >>   
   >> The resistor pack is open in all speed settings except High. It is a   
   >> common part that should be available at the parts store down on the   
   >> corner.   
   >   
   >  The blower resistor is not used for high speed.   
   >   
   >   
      
   That's correct. The resistor(s) is(are) used for all of the other speeds   
   except high. This is why the other speeds fail and high remains working.   
      
      
      
   >>   
   >> Blowing cold is a sign that the coolant is not circulating through the   
   >> heater. Either the plumbing is clogged or the water pump impeller is worn   
   >   
   > If the water pump were bad the truck would overheat.   
   >   
   >   
      
   True, mostly.   
      
   There are reports of failed impellers that let the engine maintain mostly   
   normal temps, but the temps rise when airflow slows. This symptom is also   
   common when the fan clutch fails, but we are not talking about the fan   
   clutch so I did not mention it earlier because I did not want to get the OP   
   side tracked. We are not talking about the fan clutch because it will not   
   affect the heater performance ...   
      
   I agree that there would be other symptoms of a worn impeller, heat being   
   the most significant. But, the impeller can fail where coolant flow through   
   the heater core is diminished, while flow through the motor is marginable.   
   If this was the case, temp problems in the motor should crop up soon, if   
   they are not apparent already. This is why I put my money on the clogged   
   plumbing to the heater core, or a clogged core itself. My remedy for clogged   
   plumbing and/or core is to flush with a garden hose. It would be better to   
   take the truck for a professional flushing because they will properly   
   capture the coolant that comes out,   
      
   You should have read all of my first post, then I would not have had to   
   explain this all again.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)