Soft Brakes!
 

A while back I put some 33x12.50's with 15" wheels on my Yukon and noticed that the brakes were softer than before. They have even scared me a few times when I needed to stop rather shortly. The tech said that will happen with the bigger tires. He recommended going to heavy duty brakes to overcome this problem. I looked into some but am a little confused as to what I can do for HD with only 15 inch wheels. It seems that most HD brake systems have larger discs and I don't know what can be done for the 15's. Anybody have any ideas about this?

Oh yeah, my brake system has been checked out and has no leaks or any pressure drop in it.

If you are talking about "not stopping as well" then that is just the leverage disadvantage of larger diameter tires, the additional weight doesn't help either.
If you are talking about a "soft pedal".....that is different.
There are up-grade calipers that can give you better stopping w/o having to go to a bigger diameter rotor.

When I first got my '96, I noticed that the brakes seemed soft, too. Compared to my '69 with discs, it was really noticable. I asked folks on another website, and it seems that this "soft" feel is common, especially in the '96's. I suspect that it is common to all that have ABS, for some reason or another.

You can get larger brakes, but you're gonna have to have a larger wallet to pay for 'em. Check Baer, for one.

Also, you might check out the kevlar brake pads that PraiseBrakes puts out. They are supposed to be the "berries".