How cold should AC Blow?

God shops will put a dye in the system and use a black light to identify a leak. Hopefully your shop did this.
Also there isn't a specific discharge temp but there should be a temp drop of 15-20 degrees from the inlet and outlet temps,,as told to me by a tech,,,doesn't mean it's true though...

 

In A/C refrigeration class of 1984 I was told that if you get a 30 degree drop in a single pass it is doing a pretty good job. I have found that to be pretty accurate over the years. That means doors opens and controls set on fresh air. Ice cold normally comes in after you close the doors and set to controls to recirculante.

 

100 degree ambient temp and mine will blow 39-42 degrees.

 

Oscar is that on fresh air if your truck has that with the driver and passenger doors open? The best I have ever seen out of the vent was on a small grill Astro, 28F. I thank that makes it 1978 or older, the ones with POA valves. Those valves were discontinued, must have had to many problems, but they were great when they worked. Air could run back and forth between above and below freezing. Still did not outrun the greenhouse effect of the Astro. 39-42 thats an awsome a/c!

 

That's on fresh air, my recirculate door doesn't work.