Brakes and parking brake.

I had a brand new master cylinder installed on my truck over the summer. Last week was in town and doing more than normal stop and go due to holiday traffic. My brakes are there at first but can feel my pedal leaking down as I'm slowing down, if I don't pump it, I run out of pedal and won't stop! Now, I know I have a rotor that needs to be turned, has some vibrations as I'm on the brakes, wondering if I blew a seal in a caliper or something? I'm not a mechanic, but don't mind working on my own stuff. Just need to know what's going on and why with the master cylinder being replaced less than 6 months ago. Also, wanting to replace my parking brake cable on it as well. The on directly attached to lever under steering wheel. My tacoma is a 97.5 2.7 liter 4x4 reg cAb. It does have the efi if that makes any difference in models or anything.

 

Well that's an interesting situation. Are you losing brake fluid?

Sounds like you have air in the system but without more information it would be hard to say. Check your vacuum lines too as a leak in vacuum will cause the booster to act up.

 

Yes loosing fluid. But can't find a leak on any of the lines or where lines connect to master cylinder. And I'll check out the vacuum lines. Anyone know how many there are?

 

did you use a OEM Toyota master cylinder, ive read about a lot of aftermarket over the counter master cylinders that fail or are not as good right out of the box as an oem, I had the mushy pedal feel on my truck, its better after you adjust up the rear brakes and bleeding the brakes could help

 

Sorry for such a late response.
If your losing fluid I'd start looking for an obvious leak or wet spot. Honesty I'd check to see if all my bleeder screws are tight before doing anything else. If everything is tight check the fittings that connect to the master cylinder. Lastly check drum wheel cylinders for leakage. If no external leak is found chances are the seal between the wheel cylinder and the booster has gone out.

 

What's best way to check that? And anyway you could give a little more detail. I don't mind trying to work on my truck, but I am no mechanic by any means. I know where booster and master cylinder are. But as far as braking components I'm not sure of much else.

 

The bleeders look like grease zerks. Their is one for each brake caliper and brake wheel cylinder. If memory serves me right the ones in the rear are directly above the axle on the backing plate. The front bleeders are on the brake caliper. These should be fairly snug. If there is no wetness present then it is safe to say they are not leaking.

I'm not nearly as familiar with the 97 as some others here on the forum but the braking system is very similar to the one on my 2nd gen. I would recommend looking for the brake lines exiting the master cylinder and following them while looking for damp spots or wetness. If you can carefully remove the rear wheels and the drum and look for any wetness from the wheel cylinder seals. I hate to tell you Google a wheel cylinder if you don't know what one looks like but that's the only way I can possibly explain how it looks. It's a cylinder with a double acting hydraulic puck that pushes the brake shoes.

 

I think you mean between the *MASTER* cylinder and booster. The booster is nowhere near the wheels

 

Auto correct strikes again. Oi!