Fixing 2000 toyota tundra brakes shop recommendation

[Krondor]

So I have a 2000 toyota tundra with very mushy brakes.

It all started with an intermittent braking issue where the brake pedal would be hard to press then it would go fairly soft.

I have swapped the brake booster with 3 different after market units and the brake master cylinder with 2 different after market units. The brake booster and master cylinder are NLA from Toyota.
I also bled the system the old fashioned way, vacuum brake bleeding and Positive pressure bleeding. I'm 100% sure there is no air in the system.

I have already had a shop take a look and spent $$$ on all new rear brakes and front calipers/rotors. This did not fix the issue.

I am about at my wits end with this truck.

Does anyone have any recommendations on a shop who might be able to diagnose this issue?

Thanks,
Alex

 

[Teddy]

Vacuum leak to your booster? That would generally cause a stiff pedal though. ABS module going out? Sometimes you can find a gravel road and accelerate hard and then brake hard to get the ABS to actuate and it will potentially free anything up.

 

[Krondor]

No leak from what I can find to or around the booster. The truck doesn’t have abs either… it’s strange.

 

[sinsin]

Did you ever figure this out? I have a 2000 Tundra with similar symptoms. Sometimes the brake pedal is super hard and other times it goes down to the floorboard.

I've also experienced an issue where it seems the brakes are being applied without me pushing on the pedal. I have to give it extra gas to fight the added resistance and when I let off the gas, the truck brakes to a stop more quickly than if it were to coast to a stop with normal engine braking.

My truck does have ABS though and I'm wondering if it's that or a stuck caliper/shoe. The first time the random braking happened was after I slammed on the brakes after someone cut me off. The brakes were basically locked and I couldn't move the truck. After a few minutes and restarting the engine it started going again and it's been intermittent ever since (although never as bad as that day).

 

[Krondor]

I still haven't fixed the problem completely but I did replace the rear load sensing proportioning valve with a basic valve using the kit from firstgentundra.com:

LSPV (Load Sensing Proportioning Valve) Delete Kit for Wilwood Manual Proportioning Valve — First Gen Tundra

Updated for 2024: the bracket is now powdercoated matte black for maximum longevity and corrosion resistance. Please read attached instructions for full details on this kit. If you are looking to remove your factory LSPV and replace it with a Wilwood manual proportioning valve (availa

www.firstgentundra.com

That seemed to help a good bit. I also replaced the brake master cylinder and booster with those from a T100. and that also helped but the brakes are still hard to press. Almost like there is not enough vacuum or the booster I got isn't working as it should...

 

[sinsin]

I also replaced the rear load sensing proportioning valve after noticing it had a leak. Afterwards I bled the brakes and I couldn't get anything out of one of the bleeder valves. Makes me wonder if one of the brake lines is clogged. Will have to look at it some more.

 

[blinkerfluid]

Did you ever figure this out? I have a 2000 Tundra with similar symptoms. Sometimes the brake pedal is super hard and other times it goes down to the floorboard.

I've also experienced an issue where it seems the brakes are being applied without me pushing on the pedal. I have to give it extra gas to fight the added resistance and when I let off the gas, the truck brakes to a stop more quickly than if it were to coast to a stop with normal engine braking.

My truck does have ABS though and I'm wondering if it's that or a stuck caliper/shoe. The first time the random braking happened was after I slammed on the brakes after someone cut me off. The brakes were basically locked and I couldn't move the truck. After a few minutes and restarting the engine it started going again and it's been intermittent ever since (although never as bad as that day).

This is a symptom of a brake booster going bad and / or bad MC to booster pin adj / bad pedal pin adjustment

 

[Krondor]

Well I finally fixed the brakes.

After replacing the front and rear brakes, replacing the LSPV with a manual valve, and swapping the brake booster and master cylinder with a T100 unit, the brakes still were not working correctly.

It was driving me up a wall at night and I couldn't figure out why it wasn't working. So I decided to go back to OEM. The master cylinder and brake booster are discontinued so I had to go the next available route. I took both units out of a wrecked tundra with low mileage. 15 minutes later (I am now very proficient at replacing boosters and master cylinders) and a quick help from my awesome wife to bleed the system, The brakes are fixed.

I don't know completely what was the cause but I suspect it was a dual issue. I think the master cylinder was kaput along with a seized/blocked LSPV.

I also think that the T100 MC and BB could have worked if I adjusted them correctly. I'm positive the pin adjustment was off.

 

[sinsin]

Nice job fixing it! I had similar symptoms and finally fixed mine but it was a little more straightforward.

One day the brakes were locking up while I was driving to the point where my driver side started smoking. After sitting for a minute, I pushed the pedal down (it was stiff as a rock) and then heard an audible release of air.

After that the brake pedal has felt fine but then it started squealing which made me think the rotor/pads were bad.

I finally stopped being lazy and popped the wheels off and the pads were embarrassingly low. Replaced the front pads and rotors, bled the brakes, and now the noise is gone and pedal finally feels normal consistently.