Q&A

Antifreeze does not evaporate, it must be leaking somewhere. There could be a very slow external leak which is very hard to find or you could have an internal coolant leak into the cylinders causing coolant loss. At this time there a no recalls on the dexcool antifreeze used in your Trailblazer however there have been some problems with that type of antifreeze. Try searching the internet for more information on dexcool antifreeze.

If I was you I would be changing my oil sooner than 30,000 miles. You must be putting some good expensive oil in cause I do mine every 3,000 to 5,000 miles.

i have the same problem with my car i believe its due to the water in 50-50 mix that evaporates.