Brakes are locked up on my 2001 chevy Silverado 4wd p/u. All 4
calipers are compressed, brake pedal feels like theres pressure on it.
Answer: If all the brakes are locked up, there is a few possibilities that
can cause your problem. There could be a contaminated substance
in the master cylinder along with the brake fluid. Usually someone
adds power steering fluid or another fluid where it's not supposed to
go. This will cause the entire brake system to fail. The rubber seals,
rubber brake lines and caliper boots all distort and expand due to a
foreign substance. This will eventually cause all the brakes to not
work and act like they are locked up. This will also ruin the ABS unit
as well. A very expensive repair, as just about every single part on the
brake system needs to be replaced. You can check the master
cylinder cap and look at the rubber seal on it, and if it is all blown up
and extremely soft that is your problem. Another cause that should be
checked out is something binding in the brake system. A stuck master
cylinder or rod, or boost unit can do this too. Emergency brake cables
should be checked too. This last one is doubtful, but you could simply
have seized calipers that need replaced.