TUNDRA BRAKE UPGRADE PROBLEMS?

I too had a soft pedal after the inital install. I used a Motive pressure bleeder and was able to bleed out any residual air in the system; no more soft pedal. One of the best upgrades I have ever done to the truck.

 

My Tundra front brake upgrade is also great. No problems.

I followed the Adventure Taco guide and used his caliper hose kit.

I believe that the additional pedal travel is the result of needing to push more fluid into the larger tundra caliper pistons. I too, find that a second pump really brings the pedal up to the top for a real solid braking feel.

I asked Adventure Taco about a different master cylinder which, with a larger diameter piston would push a greater volume of fluid, but he said it wasn’t necessary.

Mike

 

Figure I’d update here again. I did the rear brake shoes and cleaned/ repositioned the parking brake adjuster. This made a pretty significant improvement, the rear drums were pretty worn. It never felt like you could lock up the wheels, but it was much firmer. I’ve driven on this setup over the past 4 months, but in the last few weeks the pedal has gone soft again. I’m wondering if maybe the master cylinder on my truck is undersized for the upgrade (mine is a 99).

 

Maybe a brake fluid leak?

 

I thought as much myself, but all wheels and lines look good and the master has a full reservoir

 

Air in the master cylinder? Did the MC go dry during the tundra brake install?

 

All I can say is that the deceiptions of the soft pedal are so common and so specific/identical, it’s hard to think it’s anything but the obvious need for a bore MC. Just finished mine with the adventure taco kit and Amazon caliper - Toyota everything else. Replaced really the entire front suspension with OE’. We bought the truck new in 03 and intend to keep it. Great instructions from adventure taco and the kit is great. I would love some options for larger MC, if anyone knows.

I have the same as everyone else. First pump goes waaay down before any brake but if you give it a second pump, it firms up a bit.

options?

 

I still have not found a fix. Switching out the master cylinder for the smaller bore is just not as easy as it would seem because the brake pedal linkages are totally different. It would require some significant modifications under the dash.

after having lived with the upgrade for a while, I’d just as soon go back to the stock form. The soft pedal feel bugs me to this day. If anyone does find an aftermarket master cylinder with the smaller bore that fits without pedal modification I would jump all over it

 

Bummer lots of big brake upgrade woes. My little regular brakes are not jealous.

 

Yeah if there had been more discussion on here about the troubles with it before I did it I wouldn’t have gone through with it. It definitely is not just a “bleed the system” type problem

 

PS here’s a pic.

 

I had no problems.
I did do a very thorough bleed and had already deleted the Load Sensing Proportioning Valve.
Truck will stand on its nose, or locks up all four tires. Seatbelts hurt now.

 

I had that same problem after my upgrade and only until I used a pressure bleeder was I able to get the brakes to feel like the stock pedal. I did a 2-man bleed over 10 times with the same result.

I suspect that there were air bubbles trapped in the new calipers, which the pressure bleeder and tapping the caliper got rid of. It was a night and day difference.

That pedal feel that you are experiencing is not normal with these brake upgrades. The tundra brake upgrade is still a top 3 upgrade on these Tacomas IMO.

 

I did my normal bleed and when I took it for an alignment (did all suspension same time), they offered to use their brake bleed machine that does a complete flush on the system…same results. He said the mechanic brought it back in after the first bleed, thinking it still had air..but didn’t get it any better.

 

Does anyone get a squealing only in reverse while lightly braking. For example, if I'm on a hill/driveway and the truck rolls down backwards in neutral with slight braking. I tried cleaning brake dust, lubricating the shims, trimming dust shield for clearance, etc.

 

I get a squeak in reverse when it's cold in the morning. Goes away after the first stop.

I had a lot of trouble with spongy Tundra brakes and needing a double pump. The stockers were way better.
Then a friend showed me his new high perf four piston calipers. They had two bleeders for the inward and outward pistons.
Maybe there is trapped air in the outward pistons.

Using this and a pressure bleeder did the trick.

$15 DASBET Disc Brake Pad Installation Spreader Caliper Piston Spreader Tool

Amazon.com: DASBET Disc Brake Pad Installation Spreader Caliper Piston Spreader Tool : Automotive

First I removed a rotor and then loosely installed the caliper. Then install the caliper spreader. I adjusted the spreader to contact the pads. Next I pressurized the master cylinder to just 5 PSI. Then I opened the bleeder and then compressed the pistons with the spreader.
Many bubbles came out. I then closed the bleeder and carefully retracted the pistons with the spreader to their original position. I repeated the compression and retraction till no more bubbles. Then repeated for the other side. Now the brakes are very firm.

How I adjusted the portioning valve is bring a friend to a road with no traffic. Disconnect a rear brake ABS sensor to temporarily disable.
Have your friend down the road to where you can accelerate to highway speed. I had my friend behind a power pole for safety. Firmly brake till a tire locks up. Have your friend notice if a front or rear tire locks. Adjust the portioning valve so the fronts lock just before the rears.

Hope this helps

 

cant wait to do the tundra brake swap on my taco