1995 GMC Savana Pulls to right

Vehicle pulls to right when applying brakes. Checked all steering components both while vehicle was running and not, while on the ground and in the air. Iinner & outer tie rods, center link, pitman arm, idler arm, upper & lower ball joints all checked out OK except the idler arm. It showed some wear, excessive movement so I replace it and greased all components. Hoping that this was the problem, I took it for a test drive. It still pulls to the right, but not as bad. Front end was aligned 1500 miles ago. Tires have 15,000 miles and are wearing true. Brakes were done only 2500 miles ago. Pulling started about 500 miles after the alignment and progressively got worse. I'm thinking of replacing the right front flexable brake line. The caliper is free, not hanging up. The only reason I don't think it's brake related is when you drive backwards the steering wheel wants to make a hard left turn. I mean you have to fight it to keep it straight. It's gotten to the point of being dangerous like something really is worn out or broken, but everything like I said, is tight ! Any ideas, Thanks, Tom