First of all hello everyone very nice to be here! This is my first post in the forums😊 My question for you guys is that i believe either my master cylinder or brake booster have gone bad..I went to drive the truck early this morning and noticed the park/brake light stayed on after i applied the brake pedal which basically went all the way down to the floor.

 

Either out of fluid, which would indicate seal leaking on the calipers, or brake line, or the master cylinder has an internal leak.

 

Thank you Kevin, i appreciare your response. I will inspect the calipers and just replace the Master Cylinder as well. I found an AC Delco one for $40 on Amazon Prime..Truck has 148000 miles so i seriously doubt it's the brake booster. Thank you and have a great weekend.

 

with kevin, i would inspect the brake fluid level. anywhere in the brake system could leak fluid and cause the light to come on and brake pedal to go to the floor. look at the inside of the rear wheels and see if they look wet this would indicate a leaky wheel cylinder if you park on pavement you would also want to look at the ground for a wet spot. if you cant find one add some fluid and have an assistant press the brakes and see if you can hear/see the fluid coming out.