Honda Repair: brake sabotage, dot 5 brake fluid, freeway speeds

Question
My Wife had the master cylinder replaced in her 95 Honda Civic. A few days ago the car started shaking while she was drivng at freeway speeds. She took it back to the mechanic who previously worked on her car and he drove the car and initially thought the brakes were acting up again, and maybe the master cylinder he installed was defective. He later started working on the brakes and said he found corrosion on all the rubber parts of the brake system, and he removed  blue fluid from the brake lines. He asked if anyone besides him had worked on our car since he saw it, we told him no. He said a lot of the corrosion has occured since he last worked on our car and he suspects sabotage. Have you heard of someone pouring something into the brake line to corrode them.

Answer
Hi Gerald, and no i would not suspect sabotage. How long was it between the time the master cylinder was replaced and the time you took it back to the mechanic? Months? Days? Please be specific. Do you live in an environment where it was snowy? Muddy? How is the car driven? Rough or at high speeds with a lot of abuse? Brake fluid is very corrosive towards painted surfaces and I would not suspect that it would damage rubber grommets, etc. Did he find "rust" or "corrosion"? Blue fluid generally indicates DOT 4 or DOT 5 brake fluid which is generally used in racing environments because it can withstand high temperatures and not fade compared with DOT 3. If you had your car serviced at a local in-n-out lube specialist they could have potentially topped off your brake fluid with a different type of brake fluid as well. This might conflict with the brake fluid you had originally in the vehicle. (Very slim possibility in this situation.) I would do a complete pressurized bleed of the brake system and refill fluid. Clean all areas by pressure washing all brake lines, including the master cylinder. To remove the corrosive ailment from all surfaces. Continually inspect all areas. Was the Master cylinder replaced with an OEM unit? I hope this helps your problem and let me know if it does not...