I think I know the answer to this but I'm going to check with you guys.
Recently driving my Landy I have had a problem of the break pedal being rock hard and it seeming that all the brakes on. The engine has to fight to get moving and it stops if braking when freewheeling (It doesn't pull to any side. Brakes evenly.
Sometimes if I stop for 10 minutes the problem completely goes away. Sometimes it doesn't.
I have changed the brake fluid in case of contamination but the problem persists.
Its the Master Brake cylinder isn't it?