So i've been told GM used 2 different brake options on the NBS trucks. In particularly my 1999 Silverado ECSB 4x4. Now I was told that were 2 different packages available. My only problem is I can't find anything on the differences of the two braking packages. Now as to why I'm searching for this info is because a while back I ordered a set of cross drilled & slotted rotors for my truck and then was at the last minute sent out of state for work before they arrived. Well now that I've finally returned 2 1/2 months later I found out the rear rotors dont fit, the rears I got, while the correct diameter and bolt pattern are thicker than my stock rotors. As for the fronts I was so pissed I didnt even check to see if they were the same.

So my question to you guys is, what would be the difference between the two braking packages offered? Was it just in the rear brake setup or all around? Since I dont have the option to sent these rotors back I might as well upgrade to the thicker rear rotors I now own.

Thanks In Advance
-J
99' Silverado ECSB 4x4

 

So I checked into some things and found out the front rotors appear to be the correct ones, while the rears are 13" diameter and 30mm thick, which appear to be the SUV rear rotors.

If my assumptions are correct then I should be able to get rear calipers and caliper mounting brackets from say a 01' Tahoe 4x4 w/ 5.3 and should be good to go. Does that sound right?

 

I believe the rear brakes are different based upon the GT4 or GT5 option. I think it is tied to the rear end gear ratio. I have 3.73 and I have the larger rotors. I once got a set of the smaller ones by accident. This on an 01 Tahoe. Hope it helps.

 

Ran into similar issues w/ PowerSlots and Hawk pads when upgrading my 2000 EC Silverado 2WD.

 

I did find some info based on what your were saying Bish about the GT4 & GT5 options. It turns out that the rotors I was given are from the GT4 option which are the thicker rotors. The option is only listed for the SUV's though, not for the trucks, but i've heard of people upgrading to the SUV setup. So what I plan on doing is using those rotors while upgrading my calipers to the 2 piston units that were used in the SUV's such as your Tahoe. The only thing I need now are the caliper mounting brackets and a little luck that they attach to the rear end the same way, which they "should" as I believe your Tahoe also utilized the same 10 bolt rear as the 1/2ton NBS trucks.

 

I believe you are correct in that the rear end on my Tahoe should be the same one used in the 1500 series pickups. BTW, I replaced all 4 calipers at about 140K with reasonably priced units from Napa. I just don't like to screw around with brakes as my life may depend on them...especially the way I drive

 

Looks like i'll be taking a visit to Napa to pick up some calipers.... the only thing i'm dreading is going to the dealer for the brackets as i'm sure they aren't giving them away cheaply.