Brake issue

Hey guys! I need some help. My brakes worked fine on my way to work. On my way home they did something weird twice at the beginning of my drive. When I applied the brakes the pedal pressed normally then dropped a little fast and then back to normal pressure. The pressure in the pedal builds when the brakes are pumped up and doesn’t feel squishy. After doing this twice at the beginning of the drive it worked fine the rest of the way home. I did keep my hand ready by the emergency brake just in case. When I got home I looked around under the truck and I don’t see anything leaking. It doesn’t appear to be leaking around the master cylinder either. The truck is a 2004 Tacoma Doublecab with Tundra WL calipers on the front. I put them on many years ago and have never had an issue with them. I changed the fluid last year. The truck seems to be running normally. Any help would be appreciated.

 

I meant to put this in the 1st gen section!

 

I didn’t check the wheel cylinders yet. Thanks John!

 

Absolutely sounds like a bypassing mc. If you slowly gently press the pedal, it might go to the floor. If you suddenly slam it hard you’ll probably get pressure.

Guessing you already looked at the mc reservoir, it has fluid in it?

 

Yes. Master cylinder or (I hope not) power boost assist. The power assist isn’t cheap. The master cylinder is.

 

Yes, the reservoir is full.

 

Cheap sounds good!

 

Have you ever changed your rubber brake hoses ??

That might be something else to look at?

How does the parking brake feel when you apply it?

 

I have replaced the hoses. The parking brake cable could be replaced. It is stretched out. The parking brake does work though.

 

I just wanted to update this thread. The wheel cylinders looked fine so I decided to replace the master cylinder. So far I haven’t had any more issues.

 

Just another update! The brakes are still working well. My anti-lock brakes had been coming on a lot. I had actually thought about removing the abs, but it seems much better now with the new master cylinder. Maybe the internal leak in the master cylinder was affecting the abs?