2017 Tahoe - Brake pedal to floor - only once

[bchandler02]

Hoping someone here can give some ideas. I'm not a GM guy but a family member has a 2017 Tahoe. Last week, after driving the highway for about 30 mins, then city streets for 10-15, they turned into a parking spot. When they did and hit the brakes to stop, the pedal went to the floor and it barely had any braking power. It has < 50k miles on it. 

 

Truck was towed back home and by the time it got back, everything was fine. Had a local shop look everything over and they couldn't find any issue. Also talked to a GM dealer and they had no idea as well. 

 

So far, nobody can explain why this ay happened only once. My first instinct would have been a failed master cylinder, but that would not explain why everything has been fine since. 

 

Anyone have any experience with this or ideas? 

[mjm-1957]

Replace the master cylinder. We have had more than a few like this.

[JimCost2014]

23 hours ago, bchandler02 said:

Hoping someone here can give some ideas. I'm not a GM guy but a family member has a 2017 Tahoe. Last week, after driving the highway for about 30 mins, then city streets for 10-15, they turned into a parking spot. When they did and hit the brakes to stop, the pedal went to the floor and it barely had any braking power. It has < 50k miles on it. 

 

Truck was towed back home and by the time it got back, everything was fine. Had a local shop look everything over and they couldn't find any issue. Also talked to a GM dealer and they had no idea as well. 

 

So far, nobody can explain why this ay happened only once. My first instinct would have been a failed master cylinder, but that would not explain why everything has been fine since. 

 

Anyone have any experience with this or ideas? 

Welcome to the site.

 

Have them check the vacuum pump, known problem for the K2 trucks and SUV's of same years.