Braking Issue...Advice Please

I have a 2003 PreRunner, great running truck and I use it as my daily driver. 3" suspension lift with 33" Wild Peaks.
Lately when I need to brake quickly the peddle is rock hard and the truck is very slow to stop. The peddle will slowly go down but with a lot of resistance. Under normal brake use it seem fine and basically the same peddle reaction and stopping ability.
This has lead to some scary situations the last couple of days, I installed brand new pads on the front but that did nothing to remedy this issue, also the fluid level is full. Any of you Taco experts have some ideas what may be going on? Thanks!

 

Not being there to see what is going on I can only give general advice. I suspect that the pads you put in are of a different compound. The pads and rotors need to "seat" for optimum braking, this is why it is recommended to machine the rotors when new pads are installed to aide in the seating process. The friction material has to come up to temperature before it works best. Bake pads/shoes have a number of different ratings, one of them is its "initial grab" and the other is its fade rating. These are the letters that are inked onto the friction material. They go from A to F, if I remember correctly, AA being the lowest inital grab and the lowest fade rating with various combinations between. The manufacterer usually has this figured out for you, the guy at the parts store doesnt care.

Brakes are a "system" meaning that there are multiple parts that make it work, again, not being there it is difficult to point to "the" problem.
Is the brake master cylinder full and what does the fluid look like? ... dark means that it needs to be flushed.

If the rear shoes are out of adjustment/worn this will effect the overall braking ability of the truck. To check for rear shoe adjustment pull the parking brake out slowly and count the clicks until it get firm... 18 clicks I think is normal. If it comes all the way out and never gets firm, thats a problem with the back brakes.

With the engine not running press the brake pedal numerous time to bleed the vacuum out of the brake booster.
Press the brake pedal lightly and hold your foot there for a minute. If the pedal starts to drop the master cylinder needs to be replaced. A slight pressure allows the brake fluid to go around the outside of the seals whereas a quick press expands the seals and it works as designed.

take your foot off the pedal and let it return. Put your foot on it again and start the motor. The pedal should drop "a little". This tells you that the booster diaphram is ok. The booster should hold vacuum for a while, over night usually.

 

1. Your brakes are not equipped to handle 33s (ask me how I know, many scary situations with brake fade as you describe). Highly suggest tundra brake swap, for your safety, or going down in tire size.
2. You need to bed in your brakes properly. There are many how-tos on this.

 

Brake Booster not working properly???

 

While the Tundra brake upgrade would be a good thing overall for the larger tires, it doesn't sound like the OP's issue is brake fade, since it is an immediate reaction and hard to press on the pedal.

I'm thinking the brake booster, too... I haven't done much work on mine, so I'm not an expert on how you'd check it, but I'd do a little searching on how to do that, first, before you go throwing Tundra brakes on.

 

I have had the 33" for a year and no issue with stopping, either hard braking or under normal situations. When this first began I inspected the rotors and pads, they were fine however I elected to install new rotors and OEM pads...no difference in the hard braking problem. After more research and couple of yall were absolutely correct, it was indeed the booster. I replaced that and all is fine when stopping. Thanks for the all the suggestions fellas.

 

Glad you got it fixed!

Now time for Tundra brakes, lol

 

@jbrant Yep!