Excessive brake pedal travel before bite. Am I bleeding wrong? Something Else?

Hi all,

I bought myself a 2008 2.7L Regular Cab 4x4 a few months ago with 160k on the odometer. Recently, I swapped out the brake lines to stainless steel, and ever since I feel like I have excessive brake pedal travel before any bite. The initial ~1/4 of brake pedal travel feels like it does nothing. Brake pedal travel was definitely still a little high for my taste before (one of the first things I noticed on the test drive), but I believe the brake pedal feel either hasn't changed or has gotten slightly worse. Drove a friend's 2011 TRD Sport and the brakes felt firmer and with earlier bite.

The pedal is hard after a few pumps when the engine is off, and soft once I turn on the vehicle. I still have enough brake force, the pedal simply feels soft and requires travel. I don't believe the pedal is spongy, though I do not really know what spongy brakes feel like. I'd like to add that I torched the front calipers to remove and replace some broken off, rusty bleeder screws. Any thoughts on what my problems might be?

• Glazed rotors/calipers from torching the old bleeders to remove them
• Preexisting vacuum booster/master cylinder issues
• So much air got in the lines that I just need to keep bleeding (went through about 1.5 32oz bottles of DOT 3 between the line swap, fluid flush, and bleed)
• Rear shoes need adjustment
• I'm messing up my 1-man bleed somehow
• Anything else?

Thanks!

 

Since the scope of your work had opened the system up I would suspect air in the ABS System that will require a scanner capable of opening the ABS Solenoids in order to bleed the air out.

For the long travel of the pedal the most likely suspect is the rear shoe adjustment.

 

OP, see my post #29, and especially my Post #29 here https://www.tacomaworld.com/threads/brake-bleed-question-advice.713661/page-2#post-25413867

Make sure you bleed the MC on the truck as prescribed. It was the source of my issues on my '09.

 

Thanks for the replies all, I'll try the rear shoes adjustment and MC bleed to see if that helps before investigating the ABS system. Quick note: Once I bleed the MC, I'm assuming there may be small pockets of air in the brake lines connected to the MC that need to be pushed fully through the lines and out the bleeders. Anyone have an estimate of how much brake fluid this will be? Few pumps? Half the brake fluid reservoir?

 

when you bleed the MC as shown in that diagram, how do you reconnect the brake lines without letting air back in the MC? Seems like the second you took your fingers off, air would get back in?

 

Notice that the official procedure says to do 3 or 4 times. I have done this a couple of times now on others and it seems to work. Not sure how to answer your question though as I would have to tear apart one and study the thing....

 

Did you start your bleeding in the rear and then come forward?

It's worth a shot, along with the rear adjustment.

Like @Jimmyh mentions, if the ABS has air, it's near impossible to clear without a special tool.