Brake issue - I could use some help here.

I have a 2022 4x4 Platinum Tundra with a 1.75" Rough Country leveling kit and 285 60R20 Cooper Discoverer A/T tires.

From brand new, my truck never hit 14mpg. I primarily do in-town driving. The best it ever got was 13.8 during the first few thousand miles before I added the leveling kit and tires. From there the mileage dropped to 12.8 mpg. A couple months ago, and 18 or 20 months after I did the work, the mileage started steadily dropping by 1 to 2/10th per week. I brought the truck in for the 25K service. They said it was fine, it was just the bigger tires and "lift". I asked "why now all of a sudden?". No real response. 2500 miles later, I am now at 27.5K and the mileage is down to 11.2 and I am feeling a vibration in the seat when I brake anywhere over 20 or 30 mph, I assume it is an issue with the rear brakes so I bring it in. They tell me the rear brake pads need to be replaced and all four rotors are warped. I said again "I only felt the vibration in the seat, not the steering wheel. In my mind, it was a rear brake issue but I let them go ahead and turn all four rotors. I suggested they may as well replace the front pads but they told me they measured "14" so no reason to replace them. They again tell me the engine is performing as it should and there are no performance issues.

IMHO, 27.5K is extremely premature. I have had a lot of vehicles in my life. The only one I ever had to put brakes on sub 30K miles was an XJL 5.0 Jaguar. Other than that, I have owned many with over 50K that haven't needed brakes. my 2018 Tundra had 33" tires, 3" lift in the front and 1" in the rear. It got 13 mpg. I traded it with 54K miles and the original brakes.

My thought is this, somewhere prior to the line for the rear brakes splitting side to side, there is a proportioning valve or maybe even the master cylinder preventing the brake fluid from releasing the rear brakes. That would explain the rotors being warped due to overheating (not the fronts but I had no vibration out of the front), the pads being worn and the fuel mileage being down without the engine throwing a code because it is working fine. It is just working too hard. I am guessing the Electronic Parking Brake and the button on the console to apply the brakes if you are too tired to hold the pedal (I know, right...but it does come in handy) are working off a separate set of pads in the read rotor but I really don't know if one of those could be the issue.

I told all this to the Service Manager, not really caring about the $500.00 they were going to charge me. I am worried about the brakes having an issue. He gave me the exact answer I would expect from any dealer at this point. "I called the factory rep. He says its a wear and tear issue and not covered". That had NOTHING to do with what I was suggesting. Of course, he went on to say "they put the scanner on the truck and the engine is running fine. You can come pick it up." I am beginning to understand what my wife feels like when she says "you didn't read my email / message did you?!"

So, I am throwing it out there. Has anyone else experienced fuel mileage this low or brake replacement this early? Does my theory make sense? Any advice on how to escalate it? I had a friend who wanted the truck, I was going to buy a new one. I can't sell it to a friend and feel good about it, I am not anxious to get another one with the way this issue is being ignored so that crushed the sale and, I was first on the list for a Land Cruiser for my wife but I don't want anymore first year runs. I thought that issue was in the past but apparently it is not.

Thanks everyone. I look forward to hearing your reading your responses.

 

Thank you. Mine is the same. At least I know I am on the right track. My issue is both sides apparently wore evenly so it must be something keeping pressure applied to both. What sort of mileage are you getting?

 

Asking @Eurodriver what mileage his shitbox gets......thats funny right there.....maybe not the best person to ask (37's, beat to death off road, large vent holes in quarter panels, etc.)

 

I think your idea of a "grocery getter" may be different than mine. Either that, or your grocery store is much more difficult to get to than mine is!

 

@1Exyankee - A friendly fyi - No seperate rear pads for parking brake or Hold. Parking brake is a motorized threaded plate that mechanically pushes the brake pads into the rotor. Hold is holding brake pressure through the normal brake lines.

 

If you have a temperature gun, try hitting the each wheel brake areas as soon as you park to see how hot they are. Could be a sticky brake overheating the rotor (causing vibration when braking) and pulling your mileage down. Much like Euro's description!

It is a truck, but it should be able to get you closer to what Toyota has claimed in the brochure!

 

Brakes can be a pain in the @ss... You need to take it for a drive and feel the rim by the hub.
This will tell you if the brakes are even working. Heat is generated everytime you hit them.
If they were dragging then you'd smell those pads burning up.

As for the vibration... Thats going to take a bit of detective work. Rotating the tires would be a start to see if the vibration changes.
Driving hot brakes through water is never a good idea. (thermal shock)

If you have a small mirror you can inspect the pads and see how much meat is on them.

 

I am keeping an infrared digital laser thermometer with me and making note of the temps after trips. I haven't noticed anything in the range of what I would call overheated yet but the pads definitely look to me to be overheated. Whatever it is doesn't appear to be happening all the time. I have attached pics of the pads. From my experience, they appear overheated. I believe the cracks down the middle of two of them also support that.

 

Are those cracked pads from the inside where the e-brake pushes on the pad? Looks very suspect that you have 2 cracked pads! I haven't looked too closely at the e-brake setup or how they self adjust.

 

They didn't tell me. It was my assumption that those were the inner pads but I will take a closer look when I get home to see if the pistons left a mark.

 

Here's another possibility although remote, the cruise control system can and does aggressively apply brakes when coming upon a slower vehicle as well as using the set/coast button to slow set speed. I've found it may be prudent to hit cancel instead in those situations to mitigate excessive braking verses letting cruise system slam on the brakes

 

I also would disable the automatic park brake function that engages park brake every time it's placed in Park. Just hold the park brake switch in the release position for a few seconds will disable the automatic park brake function

 

Yeah you got some nice fault lines in them pads.

 

I appreciate the thought on both points. I do the large majority of my driving around town. I don't recall when the last time I might have used the cruise control was. I do notice the automatic parking brake coming on when I back into my driveway but it rolls freely even if I just put the truck in neutral and let it roll out.

 

In response to post #11 from PBNB, both of the cracked pads are the outer pads. The two with the marks from the caliper piston are not cracked.

 

Yes I do Tom976. The problem is, I don't thing that's my fault. The Toyota store does.

 

I would ask the dealer "how do I overuse or abuse the rear brake pads?"
Seriously....

Its not like we have an emergency brake to hold and light the tires up.
So how can I abuse the rear brakes??

Aggressive stops? Ok maybe... Wouldnt the front pads get the brunt of the abuse since they primarily stop the vehicle?

Faulty pads? Maybe...

But as others have said, if the parking brake is engaged slightly, that can cause them to heat up.
Since we have no manual way of having them engaged slightly.... how is this your fault?
The emergency brakes may be out of adjustment?

 

Just to close the loop, once the brake pads were changed, compressing the pistons in the calipers must have freed up whatever was causing the rear brakes to bind. The MPG jumped to 15.4 on the highway which was a 4 MPG improvement immediately. I had called Toyota brand engagement center. They issued a case number and communicated with the store but no one at the Brand Engagement center has any mechanical experience so they really didn't even understand my issue. When the mileage improved that much directly after changing the pads, that should have validated the fact that the rear brakes were binding. To date, one month later, I have not heard a word in the way of follow up from anyone at Toyota. I traded the truck in for a variety of reasons, for a 2024 Platinum Hybrid but, I am not happy at all with Toyota's customer service. It is the first and only time I have needed them and in my opinion, they dropped the ball. I also only received one key fob with my new truck. I was told once I registered the new vehicle on the app, Toyota would be in touch to find out which store I want the second key delivered to. I then have to go pick the fob up so they can program it. To me this is a bit reckless and petty. 79K dollar sticker and if I lose my key I am hosed. Someone should rethink this policy.

 

Did you turn on/off the auto parking brake feature after? I turned mine off after changing pads and I swear the truck feels lighter/quicker

 

I'm not sure how there's so much trouble with the second keys for 2024s. I was able to get my second key for my 2024 within about a month of purchasing the truck.