[tristor]

Brake fluid is not flushed due to heat cycling, that is what bleed maintenance is for. Flushing every 2 years is because brake fluid is hygroscopic (absorbs water), and even brake systems are not perfectly sealed. Water in the fluid reduces its effectiveness and can cause rusting in the brake lines, leading to failure.

EVERY vehicle should have brake fluid flushed every 2 years. That Tesla recommends 4 years is straight out incompetent.

[m463]

My manual says:

Fluid Replacement Intervals

Do not change or top up the Battery coolant or brake fluid. Tesla service technicians replace fluids at the regularly scheduled service intervals:

• Brake Fluid. Every 2 years or 25,000 miles (40,000 km), whichever comes first.

• Battery coolant. Every 8 years or 100,000 miles (160,000 km), whichever comes first.

[tristor]

Those seem like very reasonable recommendations. Thanks for sharing that. I have never read a Tesla owner’s manual, so I was replying to what was shared previously.

[fragmede]

On a system as critical as the brakes, I highly doubt they yolo just guessed and said, eh, just make it 4 years, that sounds good. I find it far more believable they did extensive testing of the brake system, which they build, and thus know just how much water is and isn't getting into the system, and what a good fluid replacement interval is.

Or maybe everyone that works there is an incompetent monkey and they never test anything, ever. It's probably that, definitely. That's also why we see so many stories in the news about 5 year old Tesla's brakes failing. Given that we all know how long full self driving has been promised, I'm sure we'll get those news stories any day now.

[tristor]

Like anything in safety critical engineering there are margins of safety. Seal failures in the top end of the brake system can cause water ingress without immediate impact on the braking system but will eventually cause hard lines to rust through, causing sudden and catastrophic failure of the braking system.

The hydraulic portion of the braking system in a Tesla is not significantly different than any other passenger car, so yes, it’s utterly incompetent to recommend twice the maintenance interval.

[mantas]

Maybe Tesla is just hyper-focused on Silicon Valley? I could see brakes fluid lasting that long in such a nice climate. In Northern Europe where lower part of the car is in salty water bath for 6 months a year… Checking brake fluid LEVEL every 4 years feels like looking for a trouble.