Brake pressure lost or not enough

Im not loosing any fluid mines fully topped off

 

My 2009 4 banger will lock 'em down it the rear if I slam on brakes.
You definitely have an issue.
Check the rear brake drum cylinders as well.

 

Let me see what i can do probably just start changing parts

 

If the rear cylinders are leaking you will know by inspection.
They are visible

 

I have checked them they are all good no leaks

 

My 06 auto has a soft pedal to. And under a hard brake i dont think it would lock up anything. I found my drums a bit out of adjustment and fixing that really improved things. But it was not long before the problem came back. I have all new hardware and its all free moving but still the adjuster seems to not be working. I cut a window in my old drums so i could see if everything was working right and i found the amount of pad movement needed to rotate the adjuster is just unrealistic. So every time the shoes had a bunch to make up. Now this is with crap parts store parts kit and I hope thats just the problem. Will see how oem turns out.

But when the rear was adjusted up close the braking feel and performance was great.

 

Did you do the rear brakes just before this started happening? Are the brake adjusters going the right direction when they adjust? I see that the right and left rear adjusters do have different part numbers so if they are on the wrong side, they can rotate in instead of out and increase brake pedal travel a lot. When you remove the drums, is it really easy to do with no dragging of the shoes across the drum? I believe they turn in different directions.

 

http://www.ttguide.net/on_vehicle_inspection-485.html You can drive yourself crazy and spend a fortune when nothing is wrong.

The brakes generally have 1/4 free play, pedal to floor 6 1/2 inches and pedal reserve distance is greater than 2 inches. If you do the math that is about 4 inches give or take. The brakes are not designed to touch them and throw you threw the windshield.

If you have no leaks and the system is bleed properly you are overthinking the situation which will not only drain your wallet it will ruin the vehicle. Good luck.

 

I thanks guys let me see what i can do with my truck let me check the adjustment on the rear and check the pedal

 

OP, you have the vacuum assist type brakes that first appeared on the '09 trucks with the Electronic Rear Differential Limited Slip/TRAC/VSC/ABS and continued through 2015, as opposed to the hydraulic assist type found on the off road trucks. I had the same problem as you describe on my '09 with the vacuum assist type after messing with the brakes a bunch. What happened on mine was the brake fluid reservoir went a bit too low while doing a flush of the brake fluid and unsuspecting I got some air in the M/C itself. I followed the factory procedure for bleeding the M/C while on the truck and that followed then by bleeding each wheel line gave me solid brakes.

In Jan. of 2014 the procedure for brake fluid replacement was revised and the revision includes all the steps for this and the bleeding procedure. The revision highlights the M/C bleeding part and gives this sequence: Bleed Master Cylinder>Bleed Individual Lines>Bleed Actuator (if height or feel of brake pedal cannot be obtained).

Interestingly, the procedure does not seem to suggest that bleeding the actuator at the end is a routine step but rather to be done if the feel/height of the brake pedal is not acceptable as noted. If you have not yet solved the problem holler back and I can scan the revision and post.

A final note about brake fluid. I had a vehicle one time that seemed near impossible to bleed air from the brake system. Under magnification I noted that thousands of very tiny bubbles would remain for some time following a fill of the reservoir. I also noted that if the fluid was warm the bubbles would leave the fluid quicker, obviously do the decrease in viscosity. This led to a change in my technique. I now try to carefully minimize the bubbles produced from cascading during fills, try to have the fluid warm, and finally waiting for 5-10 min. between each filling to make sure the bubbles are gone. Works for me.

 

Hello so then I have to strat bleeding everything from master cylinder out to the tires correct ??

 

The actuator is on the rear of the truck correct

 

No, the vacuum assist, and master cylinder and its fluid reservoir are on the driver's side, but the actuator is on the opposite side, the passenger side, and sits above the wheel well. Stay tuned and I will scan and upload shortly.

 

@Taco0914
This revised procedure appeared in Jan. 2014 and applies to all '09+ 2nd Gen Tacomas with the vacuum assist booster. Trucks with the hydraulic assist have and entirely different method.

 

Ok I see the actuator is the ABS pump

 

My bet was unadjusted rears. Good luck op

 

Confusing.

I suggested the rear brake adjustment way back.

Procedure:

How to adjust the rear brake SHOES.

NOTE: Make sure you adjust the shoes until the drum locks, then back off 15 clicks. It will probably still have some drag to it. Leave it it will take care of itself. Also you may need to adjust the parking brake cable under the shifter.


Note: the plug to adjust is the Oval Shaped Plug. Not the round one. The Round one is for inspection of the shoe liner thickness.

 

I just changed the drum brake pads. I have the adjuster set at about a 1/4 inch out. Too much and it felt like the truck was dragging poor gas mileage and hot to the touch drums.
Too little and the pedal went to floor. Pumping the pedal would bring it back to normal but you had to pump every time you braked. At a 1/4 inch pedal feels right where it should be but now my parking brake isn't working. And if I press on the brake to hard to quickly the steering wheel jerks slightly to the right. Gonna replace the lines see if that works

 

I have posted the Factory Service Manual Specs for adjusting the rear brakes. Nowhere does it say a 1/4 inch. Follow the procedure and your rear brakes will function as designed also the parking brake.

Jesus, I don't know why I bother at times.

 

You're right. FSM does not say 1/4 inch. "Release the adjuster 15 notches" IMO is about a 1/4 inch.