Brakes Failed problems of the 1998 GMC Sierra 3500

About 4 years ago I had problems with my brake booster system on my truck when the brakes failed and it was hard to stop the truck. I had the brake booster replaced two times then had to have the power steering pump replaced as this is connected to my brake system. About a year after I had this work done GMC recalled the power steering pump on my truck. Now I am have problems with this system again. If I turn my truck right or left the brake activate just like you are pushing on the brake to stop. This has almost caused me to have an accident more them once. I understand from other owners that this system has a lot of problems with it and the only way to fix it is to remove this system and replace with a different type of system. I hope you can help me and other owners to get GMC to repair our brakes.