Towing with my 00 Expy?

[timotaio]

My manual says the combined weight rating is 12,500# with my stock 17" wheels and a 3.55 gear ratio, Im not sure of my gear ratio.I know I will have no problem pulling it Im just concerned that the extra 4000lbs pushing forward when i stop will heat up my rotors and warp them. anyone know what size rotors are on these? 12" 14"?

 

[AvroAero]

A 2000 with a 4.6 can tow 5500lbs braked. I tow my sled trailer thats about 3000lbs loaded and its braked. Its a heavy duty custom trailer.