Soft Brake pedal after pad replacement( Sorry long)

A few weeks ago, I had the front pads on my 06 Tacoma 4 wheel drive access cab. Everything is fine ,then last night i noticed that while I had good brakes,the pedal would slowly sink to the floor. A few pumps & the pedal was up & tight again. However , when the engine was not running the brake pedal was solid as a rock it was not going to move, just like it used to be,whether the engine was running or not . Took it back to the garage. I figured that the problem started manifesting itself after the new pads were installed . This could either be a pissing contest between the tech & the customer! ? The tech bled the brakes (nothing) I was told that These days a master cylinder fails ,ok ,now what do we do . No leaks any where The mechanic was concerned enough not to want to throw parts at the problem.When he compressed the wheel cylinder too fit the now bigger pad he might have got some debris into the cylinder itself. And now the brake fluid is slowly leaking internally ,causing me to have to pump the pedal to get full pedal again. Am I crazy ? How many of you guys can mash your brake pedal & have it gradually go to the floor, pump them up & have full pedal again.

 

Your brake pedal definitely shouldnt feel like that, should feel firm and stay firm when applying your foot. Where did you get your brakes done? there obviously is a leak somewhere or issue going on with your master cylinder

 

A place called Welch automotive here in Franklin N.C As I wrote earlier. I was told that Master cylinders don't go bad any more . When I was young I worked on my cars a lot ( I`m a kid of the 50s & 60s) If you had a pedal that was going to the floor & you could see a wheel leaking brake fluid, hey it was a wheel cylinder! If the pedal went to the floor & there was no leak ,the brake fluid was bypassing the seal inside the master cylinder ,no leak no pedal. Seems things got more complicated ,so did the bullshit! I`ll go back to them after xmas & get things done ,or I will use a different shop.

 

You should have took it to a dealer to get them done. Master cylinders do go bad still and so do the brake booster. The shop must have got air in the lines or something. They should have not even been messing with the brake lines anyways to just do a brake job.

 

In fact they never did open the system , until They bled the brakes when i returned . I knew it really would do no good anyway.

 

I agree with you and it is not normal and you aren't crazy. If the brakes were fine to begin with they should be better once you have new pads on.

from what you have said there should be no need to bleed them.

Poor statement IMO - I'd take a master tech from a mom and pop over a dealer tech any day.

he never said anyone touched his brake lines.

the proper way is to not just compress the pads and shoot crap into the cylinder. it is in fact to let the fluid drain from the valve when pushing the cylinders in.

 

Something definitely is not right or someone made a error

 

I never did get a definite answer from the first garage . I decided to try a second reputable garage in this area. They looked at it ,no leaks anywhere ,good brakes, Abs would cycle properly. However when pressed ,the brake pedal would still move slowly down. Pump thr pedal ,just a bit & it came right back up! Ok, let`s try a master cylinder. $168.00 later, the pedal still drops. Maybe, in fact I`m wrong ,but when the brake pedal is pressed ,you should be able to mash the pedal with both feet , & push as hard as you can , bring a buddy & have him press along with you ,& that pedal should not sink to the floor. It will move a little then stop. Correct? At least this shop requested that I bring the truck back in . They will put it on the lift again & look for leaks. This is getting to be a pain in the arse. BTW , On another tack altogether, They found that my engine a 6cyl 2006 model ,still used standard plugs. I was really surprised .

 

They might have used a bunch of that stop squeak stuff, its like an RTV type stuff and it almost works like a spring when a bunch is used, think of a rubber bushing between your caliper piston and your pad.

You shouldnt have to bleed the brakes when changing pads, however I loosen the bleeder screw on the calipers when pushing the piston back, and I can usually get a little bit of air from them just from regular use.
Good luck, and if the master was fin on the way in, its unlikely its bad now, but I guess anything can happen, just seems very unlikely.

 

Funny I just changed my front bearings and figured I'd change my front pads as well. I know have the soft break issue as well. Pump it once and its good for a few miles then soft again. It almost caused my to take out my garage door.

Have you ever figured out the issue yet?

 

i have/had the same problem on my 2005 just recently, i did the replacement myself and used very good ceramic pads. it seemed like i really had to press more at first the first few days (which usually it was not like that after pad replacement) but this time i think i used a little too much grease between the back of the pad and piston and feel some may have got on the outside and that was the reason. it did get batter after 3-4 days then on about the 6-7 day someone pulled out in front of me and i locked up the breaks on dry pavement and it got alot better, about back to normal. so i think alot the problem was just that grease, the only other difference is this time i did not have the rotors turned, so that i am sure also made a difference while the new pads 'adjusted' to the grooves.

hope that helps some

cheers,
disco