Spongy brake pedal after front pad install?

I had to change the front brakes pads on my 05 frontier KC 4x4 6 speed the factory pads lasted 99,850 miles. I replace them with Oreilly brand Brakebest ceramic pads. I didn't crack open any bleeder or anything just removed the MC cap compressed the caliper with a clamp installed pads and bolted...

www.clubfrontier.org

 

Thanks for the link. Unfortunately, there is never a resolution on that post. I’m going to start over with different pads and see what happens.

 

After my first brake change they felt soft. Not like OEM. I used EBC Yellow stuff pads and slotted/drilled rotors.

 

... I didn’t notice brake fluid on the floor until I was done...

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What ??
Is that a typo?

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I saw some fluid but I thought is was AC condensation. But, it was brake fluid and seemed to come from the MC.

 

Try doing a panic stop in gravel or wet grass, etc in order to activate abs module. You'll know by hearing a growling noise coming from dash. It should firm up peddle. Might have to do it a couple of times, but more than likely it will work on first try. If that doesnt solve spongy pedal then I would suspect dropped caliper hose.

 

Thanks. I’ll try that today.

 

Did you bleed the brakes in the proper order?

 

Yes. RR, LF, LR, RF

 

It sounds to me that you most probably have air in the abs module. I’m not familiar with the Nissan set up but some units need to be bled using a scan tool....dealer is best equipped for this.
There are so many little nooks and crannies in the abs modular that regular bleeding may not get it all out.
Changing pads won’t help....it’s the air that compresses that gives you the soft spongy brakes. Pads don’t compress so they have nothing to do with the problem.
Also, on many abs brake systems, it’s not a good idea to use a clamp to push the pistons back into the calipers WITHOUT opening the bleeder screw on each caliper. Otherwise the fluid could be pushed back into the abs module taking any dirt, water, crud, etc with it.
I’d opt to look for the factory procedures for bleeding the abs module.....might require dealer or brake shop intervention. Good luck.

Let us all know how it goes.

 

I really think you are correct. I don’t know how air got in there, but that’s the only place it could be at this point.

 

Did you try activating the abs in some gravel? When mine activated it instantly kicked the brake pedal back and it felt like a brick under pedal right after incident. It eventually softened up from being rock hard right after panic stop, but it's a lot better than before locking up brakes.

 

Yes, I went out on a dirt road and locked it up several times. Might try it again

 

Always open the bleeder when you force the caliper piston back. Not opening the bleeder puts extreme pressure on the master. An added plus is some dirty brake fluid in the caliper is flushed.

I suggest cleaning and greasing the caliper pins. I also use a rubber bulb to suck all the dirty fluid out of the reservoir and replace with clean.

Tt

 

Try bleeding again.
This time, open two (or all four) bleeder screws and pump the pedal very rapidly without closing the bleeder between pumps. Watch the fluid level. A second set of hands (or feet) would be helpful.

The only place I see a problem with air being trapped is the beefy lines from the master to the ABS which could form an airlock. You need to briefly have high fluid flow to push out any air. I'm not sure one open bleeder is good enough to fully clear that line. Once the air is past the ABS, it will be in the narrower lines to each wheel and can be bled out with normal bleed procedures.

It's almost as if Nissan designed it to trap air in that line. Or sloppy engineering if this is indeed the cause.

 

Thank you for taking the time for this reply (with a pic). I will definitely give it a shot.

 

I just ordered a Motive Pressure Bleeder. This will be my third bleed, but this will have steady pressure behind it.

I should give it up but I’m a glutton for punishment.

 

Ok, so I decided to change pads all the way around, even at 50% ware. After c -clamping the piston in, test drive, my brakes are about perfect, right close to the top on pedal depression. This tells me I'm about do for a good flush and or new calipers. A little build up in the piston made them sticky I guess.

 

Sounds more like you had lousy pads in there before.

It's a very good habit to flush the brake lines whenever you change pads. Everything is wide open, it doesn't add more than 5 minutes per wheel to flush them clear.

Also, open the bleeder screw before you "c-clamp the piston" so that old fluid gets drained out, rather than pushed back up into your very expensive ABS pump and master cylinder.

Flush until the fluid coming out is as clear as the new fluid going in. Use clear plastic tubing so you can monitor it.