I think my 2000 Silverado with 223,000 miles on it has a leaking heater coil. Whenever I try to use the heat or defroster, a fine mist that smells like antifreeze emanates from the vents, making it difficult to see through the windshield, much less breathe. The truck runs fine with this exception, is this a repair that would be worth the cost of repair?
You need to get some estimates from independent mechanics in your area. This is one of those cases where the part–in this case, the heater CORE–is relatively cheap, but the labor can be extremely expensive. Your truck may have easier access to the heater core than many cars do, so the labor cost may not be too excessive, but that is just a guess on my part.
On many cars, the labor cost is REALLY high. I believe that I paid something on the order of $600. (parts and labor) to replace the heater core on my Taurus–back in 1991! Only by getting some estimates will you have any reality regarding this situation and whether it is cost effective for your situation.
Just bear in mind that continued breathing of that aerosolized antifreeze is VERY bad for your lungs. I wound up with a very nasty health condition as a result of breathing that stuff for a couple of months.
Yes, it sounds like a leaking heater core. The core itself is not terribly expensive, but sometimes the labor cost is high because of the location of the core.
I’d ask your mechanic for an estimate, or if you want to do it yourself buy a good service manual and have at it.
I guess you have to ask yourself how much a working heater is worth. I wouldn’t want a vehicle without one.
By the way, I hope you’re checking the coolant level in the radiator, because the heater core is always leaking, not just when you want heat, and if the radiator gets low you could have much bigger problems.
You may want to replace it yourself (http://www.2carpros.com/forum/2000-chevy-silverado--heater-core-removal-vt227730.html) I know that where I live, it would cost you from 900 to 1300 to replace it- if the dashboard has to come out and the AC discharged. Your truck with that many miles is worth around 4500 here, so go slow and see if you can do the job. Sorry.