99 4Runner brakes are tough to push

[forest87]

I have replace the booster three times and it doesn't seem to help the problem. I assumed it was the booster and returned it as defective each time except the last.

The brakes are hard all the time, unlike the other posts where this happened at extremely low temperatures.

Anyone have any ideas?

 

[40Habits]

Just to be clear you replaced the entire brake booster or the check valve on the booster?