Brake fluid - DOT 3 or 4???

Hey everyone,

I have a 1998 Tacoma, 3.4L, 4x4, and need to get a can of brake fluid to top off the master cylinder after changing the pads. Do I need DOT3 or DOT4 fluid? I should know this, but I'm currently having a brain fart.

Thanks!

 

Dot3 should be fine

 

Dot3 and dot4 mix just fine. Hell, some brands say they are both in the same bottke. Get either, you'll be fine.

 

If you haven't done so in the last 5 years, I would highly suggest doing a complete flush of your brake system- not just top off the MC.

 

I generally run DOT4 when I swap in all cars. Have never had an issue. FWIW I run ATE TYP200 in almost everything.

 

DOT4 exceeds the specs of DOT 3

 

Not true at all. If the vehicle require DOT4, you can not use DOT3. But if the vehicle calls for DOT3, you can top off with DOT4. Not trying to be an @ss, but both fluid have different boiling point.

 

First gen Tacoma uses DOT3, you can run DOT4.

 

I would bleed and replace with dot4.

 

Just don’t run DOT5

 

It's synthetic, isn't that better

Like all synthetic oil.... synthetic is better...

Please don't

 

Everyone knows tacomas prefer all natural brake fluid

 

Yep, natural

 

Lol

 

You should never top off your master cylinder. Never...

The brake system is a perfectly closed perfectly sealed system that NEVER consumes fluid. Only if there is a leak do you refill the MC but if there's a leak youre in deep trouble. That needs to be fixed. If your MC is just low that means your brakes are low somewhere. Check your thicknesses and replace what you need to. When you replace any pad/shoe the fluid will push back up in to the MC and become full again. never add brake/clutch fluid. always replace brakes or repair components that are leaking

 

It should be printed on your brake fluid resevoir cap.

Makes sense and good to know.

 

While I wouldn't necessarily put dot3 in a dot4 system, their boiling points arent all that different.

Also, a quick Google shows that they are compatible with each other. Unless you're running mountain roads and really putting the brakes to work, 15-20 degrees ain't no big deal.

 

This thread is way longer than it should be. Dot 3 at a minimum. It's so much more important to flush your system of old fluid if you haven't, than choosing between Dot 3, or 4, or whatever your fluid of choice is. It's the same as the best oil question. The best oil is one that's changed at the product specific interval.

Leaks in these brake systems should be pretty apparent if they are around any of the fittings or external systems. The only other place fluid will sneak into without a trace is the brake booster.

Every topic has it's nuances- brake fluid included. Just make sure it's fresh.

 

ATE ftw. Thats what is in my track cars. Id run it in my truck if I wanted to bleed my brakes.....ever