What’s the most a 07 Trailblazer 5.3 AWD can tow/stop safely

In your other thread you say

Plan to install surge brake actuater on trailer to make trailer appear to have legal brakes

So you already know it's illegal, and you plan to make it look like you're in compliance? If you're in an accident the other guy's attorney will have a field day with you. And rightly so.