[truckster]

The biggest problem the Blazer has with towing is the wheelbase. If your tongue weight is 10 - 12% (which it should be), it should be within the rated capacity of the Blazer. Trailer sway is the biggest problem, and it's multiplied the longer the trailer is vs the shorter the tow vehicle is.

In short, I don't think you need to add capacity for the springs, but I would be really careful about towing at highway speeds. I've towed a loaded car hauler around town with my Blazer with no problem, but at freeway speeds it gets a little scary.