I have a 97 150 4x4 280,000 miles,,I have a problem with the braking at 60 mph if i have to stop quick,,It just does not happen,,It is a real problem when towing my boat..It does not grab , pull or make any noise,,I have plenty of pedal,,Power asst unit maybe ? how do i check this,,,thanx in advance..

 

Unhook the fuse to the ABS and try the brakes in a sandy or gravel area to see if they all lock up. Maybe you're not getting rear brakes. To check the booster, pump the pedal with the engine off, then hold the pedal down and start the truck. The pedal ahould drop, showing the booster is working. There can always be a perfomance problem with the booster even with this check but not very often.