Brake pedal goes to floor

[chevyfs]

The brakes only seem to work towards the end of the travel, in order to stop i usually have to fully depress the pedal to the floor. The pedal is also really soft with little resistance with the truck running. i'm not quite the smartest when it comes to brakes n the only thing i can think of trying is bleeding the brakes, so im just wondering what yall are thinking

 

[R Carnella]

Topping off the master cylinder and having someone help to bleed the brakes is a great place to start. Air in the system can cause you're symptoms.

 

[Goldie Driver]

Bleeding is a good idea, but my instant thought was bad master cylinder.

 

[fast 99]

If the master is full, it happened "overnight" and no work was preformed agree on the master.

 

[chevyfs]

If the master is full, it happened "overnight" and no work was preformed agree on the master.

The master holds fluid and is always full, They have gotten worse with time it seems though. The brake booster line had duct tape on it but it didn't look like it was doing much so i removed it, after that they seemed worse lmao, could a leaking brake booster cause those same symptoms by chance?

 

[Snoots]

2 person job. Have someone hold down the brake while you check out the brake hoses for swelling. Bleeding them is a good idea. What does the brake fluid look like? If it's brown I'd flush the entire system.

 

[chevyfs]

2 person job. Have someone hold down the brake while you check out the brake hoses for swelling. Bleeding them is a good idea. What does the brake fluid look like? If it's brown I'd flush the entire system.

It is pretty dark almost looks like oil.

 

[Snoots]

It is pretty dark almost looks like oil.

Flush the entire system!

 

[Goldie Driver]

The master holds fluid and is always full, They have gotten worse with time it seems though. The brake booster line had duct tape on it but it didn't look like it was doing much so i removed it, after that they seemed worse lmao, could a leaking brake booster cause those same symptoms by chance?

The way that I know to test a brake booster is to pump the brakes with the engine off, then while holding the brakes, start it up. The pedal should fall some small distance and then hold there.

If it does, the booster is in theory good, and in that example, the MC, too.

If your booster was not working you would have manual brakes and braking effort would be shall we say pronounced ?

Try flushing as per @Snoots which in essence also means bleeding as per @R Carnella and see if the pedal firms up.

 

[fast 99]

A bad booster won't cause a low pedal, just the opposite. The pedal will be hard and high. OP says it's going to the floor. From the description, replace the master. Yes, flush the old fluid out. Be sure and check the adjustment of the drum brakes.

As a side note, brake fluid should be flushed/replaced every 2 years. I use a turkey baster and suck the fluid out of the master every spring. It doesn't get all of it out but is very easy.