Brake Fluid Change Interval 30k miles?

I went in for my 30k mile service on my 2023 tacoma SR and was surprised the service desk guy said a brake fluid change was due. Had this vehicle for just over a year and have never replaced brake fluid in a previous vehicle before unless it had water in it.

The service schedule shows this as a line item every 30k miles which is almost every 16ish months apparently, seems excessive.

Everyone else also just replace brake fluid this often?

 

Seems excessive to me, too. I’ll replace brake fluid every 7-10y as long as measured moisture content stays low and everything looks OK. Never had a problem with that.

 

https://www.tacomaworld.com/threads/3rd-gen-maintenance-maps-get-300k-miles.789809/

Recommended to check for clarity at 25k.
If it is clean, I would go another 25k and check again, and replace when it's nearing 10 years old as mentioned.

 

Brake fluid is more dependent on time than mileage. I definitely try not to let it go longer than 4-5 years because I live in a humid region.

My motorcycle gets replaced/bled every 2 years because it has a less fluid and goes "bad" quicker.

 

Amazingly dealers don't always have your best interest at heart.

 

I've been getting the reminder from the dealership for the last 2 years. Truck just turned 4 years old. Apparently brake fluids are hygroscopic (water absorbing), which means they absorb moisture from the atmosphere under normal humidity levels. In the rainy PNW I may consider having it changed soon. Although, looking at the brake fluid recently, it still seems to look okay. In the past I recall having brake fluid replaced when I had major brake work done. Never as a stand alone maintenance item.

Toyota's are known for their reliability. Deciding on maintenance intervals requires some research and deciding what you are comfortable with. Lots of opinions out there. Especially when it comes to changing fluids.

 

every 5 years is my rule but if it starts looking dirty i flush the system. It takes 30 min with a power bleeder

 

Look at your brake fluid. Brand new when it comes out of the can, it's clear. Is yours?

I try to change mine at 30k so I don't have issues later.

The fluid is far cheaper than a new truck

 

Its an aggressive tactic. Brake fluid rarely fails or boils on vehicles, especially toyotas.

I usually just suggest doing it with brake pads or every 5 years.

I never sell it to customers unless its with a brake job.

 

Not needed. They prob tried to sell you a rear wheel alignment.

 

Back in my youth, nobody changed out brake fluid. That shit would be black as tar and it still worked fine.

At some point does it make sense to do so? I guess but I can assure you that it is probably more than fine at 30K miles.

 

cars have changed since the 60s

 

I understand what it means for brake fluid to be hygroscopic…I just don’t understand at which point the fluid in a sealed system comes in contact with moisture in the air, aside from having the fill cap off when checking moisture levels. If there are no leaks, and the brake system is in good working order, I just don’t see where the moisture would come from.

Since getting involved with maintaining cars (circa 1985), I’d never once replaced brake fluid as a preventative measure. Never even heard of such a thing until around 2015. I’ve also owned multiple vehicles that never once had the brake system opened/flushed/bled for any reason in more than 12 years of service for each (12yrs, 15yrs, and 18yrs respectively). Granted, I always inspect the brakes thoroughly, replace pads/shoes/rotors/drums before they start squealing, and keep properly lubricated where appropriate.

Has brake fluid chemistry changed at some point where it degrades? That’s the only thing I can think of, that would mandate replacement of fluid in an an otherwise well maintained brake system.

 

About every 2 years imo.

 

So what I've seen professionally is things fail sooner. In Toyota land the older ABS modules fail sooner and contaminate. We see it in Corollas and 1st gen tundra/sequoias.

Personally I've boiled a caliper once, and it may have been preventable if I had fluid with lower moisture.

So I agree its not critical, but it needs to be done at least every 5 years.

 

Did you take it to a Porsche dealer by mistake?

With that in mind, though, my fifth generation 4Runner brake fluid was completely grungy at 60,000 miles.

 

As the pistons move a tiny bit of water can make it into the caliper. I've never tested the moisture content of fluid in the caliper, but if it hasn't been changed in a while it comes out dark yellow with black particles floating in it. Not sure if it's moist or just cooked from the heat of braking.

I used to have a 4th gen 4Runner, and they had lots of problems with the pistons getting stuck from corrosion. I don't know if changing the fluid helps, but it can't hurt. I don't hear about the problem much with newer 4Runners and Tacomas, so maybe they changed the design.

 

Went thru the Maintenance schedule for my 2023 and no where does it call for fluid replacement.
It falls under the dealer recommends it so they can pay for those nice new buildings.
Just say no.

 

Flush it every 3 years or so

It isn't a sealed system, there has to be some type of vent to atmosphere at the reservoir, otherwise there'd be vacuum when the level goes down over time.

When you panic stop on the freeway the fluid can (and does) boil a bit down at the calipers. Haven't you seen the aerated fluid coming when when you bleed it? I have.
Regular flushing keeps the pedal firm, keeps grit out of the reservoir and keeps seals happy

No way I'm leaving it in there for years until it's all black