How long does it take for contaminated brake fluid (likely with oil) to impact the braking system and the rubber seals? We had the brake fluid flushed 5 months ago at a shop and the brakes locked up and discovered that the seals are swollen. They deny that it was them but they were the only ones that worked on our vehicle and claims that symptoms shows up in 24hrs to 10 days and not months later. Any advice that you can provide will be appreciated.