Brake Fluid types Opinions?

[2001LC]

Anyone care to give they're opinion on brake fluid types. I've used Gunk HD DOT 3 brake fluid & Castrol synthetic DOT 3 and they seem fine (no issues). I just pick up some Valvoline Synthetic DOT 3 & 4. Anyone care to share their thoughts on the Valvoline or others?

Edite 10/12/24
Over the near 8 years since I started this thread. I've found, using Toyota brake fluid the best choice. See post #8, herein!
I've found for one, Toyota brake is a heavier fluid. Apparently it also has conditions for rubber seals. IMHO: The extra cost, is worth the peace of mind.

 

[aging fleet]

I just did a flush with Valvoline earlier this week. Zero issues, solid pedal feel, and the wet/dry boiling points exceed that of a standard DOT3.

Works as advertised.

 

[trdcorolla]

When I was younger I ran Motul RBF 600, then moved to ATE Blue, then ATE (when they stopped making the blue one). Those were hard to find and pricey. Now I just use Prestone or Valvoline synthetic, whichever I see first when I need it.

 

[abuck99]

Id select Dot 4, its backwards compatible to Dot 3, and compatible with 5.1 and vice versa. "synthetic" (i assume its all synthetic stated or unstated) I dont think the brand has as much to do with it as the frequency to which you change the fluid.

I'd be interested to know who bottles the Toyota fluid for the US market. Not sure how it stacks up against the auto parts store "synthetic" brands.

Lucas Synthetic Dot 4
Penzoil Syn Dot 4
Valvoline
Pentosin Super Dot 4 http://www.pentosin.net/specsheets/Pentosin_SuperDot_4.pdf


FYI, higher performance temp resistant fluid ( like Motul RBF600 Dot4) is more hydroscopic and actually contaminates faster. When you get into the 500-600+ degree rated category you'll find you have to change your fluid more often. Mountain driving & towing will multiply this.

 

[LandCruiserPhil]

After boiling my fluid and loose my brakes once I now change my fluid one a year and only use DOT 4. You get about 10% higher boiling temp with 4 over 3 on both dry and wet temps.

@abuck99 is spot on with the needs to change DOT 4 more than 3

 

[SWUtah]

Doesn't it depend on the environment you live in I lived in Las Vegas and Austin Texas both dry so I change my brake fluid about every three years

 

[abuck99]

For sure environment, and how you use it: if you're towing, mountain driving, driving through mud, water crossings: streams etc . Should flush more frequently.

A mall crawler in the flatlands could go several years.

 

[2001LC]

Interesting, "higher performance temp resistant fluid is more hydroscopic and actually contaminates faster".

I know with Denver's aired climate, brake fluid last a long time. I replaced my factory fluid after ~10 years and it looked as clear as the new I put in.

I looked into who made our Toyota fluid a few years back. What I found is not all brake fluids are the same, factory installed cannot be bought by the bottle in the USA. IIRC it was made by the same company, but formula was alter for environmental reasons. Toyota DOT 3 Brake Fluid Composition ?
10/21/10 at parts counter Part # 00475 -1BF03 DOT 3 Polyalkylene Glycol Ether Brake fluid.


_____________________________________________________
Safety Recall A0M – Preliminary Notice back in 2010:

Some Toyota's (not the 100 series) had a recall for brake seal failure in the master. This was caused by using aftermarket brake fluid. Basically, it was believed the rubber composition of the seals were incompatible with anything other then factory installed brake fluid.

Safety Recall A0M – Preliminary Notice
2005 through 2006 Model Year Avalon Vehicles and
2004 through 2006 Model Year Highlander (Non Hybrid) Vehicles
Rubber Seal (Brake Master Cylinder Cup Replacement)
******URGENT******
On October 21, 2010, Toyota filed a Defect Information Report (DIR) with the National Highway Traffic Safety
Administration (NHTSA) informing the agency of our intent to conduct a voluntary Safety Recall on 2005 through
2006 Model Year Avalon Vehicles and 2004 through 2006 Model Year Highlander (Non Hybrid) Vehicles to
replace the Brake Master Cylinder Cup. This Safety Recall will also cover 2006 Lexus GS 300, IS 250, IS 350
and 2004 – 2006 Lexus RX 330.
Condition
• During vehicle assembly, Toyota uses brake fluids containing polymers that act as lubricants for certain
brake system components. If replacement brake fluid is used that does not contain such polymers, or
contain only small amounts, a part of the rubber seal (Brake Master Cylinder Cup) located at the rear of the
brake master cylinder may become dry, and the rubber seal may curl during movement of the piston. If this
occurs, a small amount of the brake fluid could slowly leak from the seal into the brake booster, resulting in
illumination of the brake warning lamp.
• If the vehicle continues to be operated in this condition, the brake pedal feel could change, and braking
performance could eventually begin to gradually degrade.
• Toyota original brake fluid which is applied at the manufacturing plant contains polymers and does not cause
this phenomenon

 

[Mike NXP]

Hoping this is relevant enough to post here.

Current condition : In the extreme colds my brain light tends to come on . I figured something ebrake related , maybe frozen. Decided to look at brake reservoir and I'm just below the min line so I suspect that's why. Fluid was "flushed" by Toyota while back.

I verified level by pumping pedal and doing the procedure listed on the res and the level seemed fine after that service so I didn't look back

Question : without overthinking this too much , can I simply just top off a splash of brake fluid and move on? Keep in mind it's freezing cold and I have no garage so quick easy fixes without screwing anything up is the game here...

 

[Eyedaho]

Hoping this is relevant enough to post here.

Current condition : In the extreme colds my brain light tends to come on . I figured something ebrake related , maybe frozen. Decided to look at brake reservoir and I'm just below the min line so I suspect that's why. Fluid was "flushed" by Toyota while back.

I verified level by pumping pedal and doing the procedure listed on the res and the level seemed fine after that service so I didn't look back

Question : without overthinking this too much , can I simply just top off a splash of brake fluid and move on? Keep in mind it's freezing cold and I have no garage so quick easy fixes without screwing anything up is the game here...

Yes, if your brake fluid level is low then you can top it up from a sealed bottle of the correct fluid, after doing the pedal pumping procedure to return the max fluid level to the reservoir. As @2001LC has mentioned in multiple threads, if you don't perform that procedure before topping off the fluid level in the reservoir then you will overfill it, leading to it overflowing the reservoir.

 

[Mike NXP]

Yes, if your brake fluid level is low then you can top it up from a sealed bottle of the correct fluid, after doing the pedal pumping procedure to return the max fluid level to the reservoir. As @2001LC has mentioned in multiple threads, if you don't perform that procedure before topping off the fluid level in the reservoir then you will overfill it, leading to it overflowing the reservoir.

Roger that. I wonder how the extreme colds affects the level, if at all.. I noticed I don't hear the humming/priming of the brake system under the hood currently.

Last summer it passed the pedal pump level check test. No leaks or anything .anyway, will test level properly and I'll get it sorted out thanks

 

[2001LC]

Cooled or not. The brake booster motor (humming/priming) should come on, anytime pressure low. i.e. brake pedal used/pumped or brakes just at rest extended period and IG key on.

BTW: I only use Toyota brake fluid. Unfortunately most if not all Dealership do not. They use bulk, since it's cheaper.

 

[Mike NXP]

Cooled or not. The brake booster motor (humming/priming) should come on, anytime pressure low. i.e. brake pedal used/pumped or brakes just at rest extended period and IG key on.

BTW: I only use Toyota brake fluid. Unfortunately most if not all Dealership do not. They use bulk, since it's cheaper.

Good info thanks....interesting I wonder why mines not humming currently. Its something I always notice otherwise....Maybe because the brake light is on / the fluid low its not doing what it usually does

No performance issues to note currently but I'll have to get it topped off properly soon . It's currently in hibernation mode until it warms up . The highlander is on daily driver duty for now . First time I've ever seen -30 on the thermostat

 

[2001LC]

Even when brake fluid reservoir low or even empty, booster motor/pump comes on.

 

[Mike NXP]

Even when brake fluid reservoir low even empty, booster motor/pump comes on.

Weird, I'll have to test some more it doesn't seem to be humming at all upon the first key turn.

Now to decide if I need to drive all the way to Toyota to buy their fluid or just top off with aftermarket name brand instead, just to get the level set right

Looking back in my records this was serviced by Toyota 30k miles ago . I don't think I need to service the fluid again but I do need to get the level set properly


Edit ** the brake system is humming as it should I must have just missed it yesterday. Ill focus on pumping pedal / toppingn off not .

Geez it's so annoying to hear belt / pulley squeal on these cold days especially after replacing every single spinning part with OEM Toyota not too long ago . Oh well that's a story for another day .

 

[excessive]

I have been using that exact same brake fluid in all my trucks and cars for the past 8-10 years, no complaints whatsoever

 

[Mike NXP]

I have been using that exact same brake fluid in all my trucks and cars for the past 8-10 years, no complaints whatsoever

Roger that , sounds like just top it off properly and move on . Suppose I'll make the drive to Toyota for their fluid, gives me an excuse to go to work late

 

[2001LC]

I have been using that exact same brake fluid in all my trucks and cars for the past 8-10 years, no complaints whatsoever

"that exact same" Which?

Roger that , sounds like just top it off properly and move on . Suppose I'll make the drive to Toyota for their fluid, gives me an excuse to go to work late

Weird, I'll have to test some more it doesn't seem to be humming at all upon the first key turn.

Now to decide if I need to drive all the way to Toyota to buy their fluid or just top off with aftermarket name brand instead, just to get the level set right

Looking back in my records this was serviced by Toyota 30k miles ago . I don't think I need to service the fluid again but I do need to get the level set properly


Edit ** the brake system is humming as it should I must have just missed it yesterday. Ill focus on pumping pedal / toppingn off not .

Geez it's so annoying to hear belt / pulley squeal on these cold days especially after replacing every single spinning part with OEM Toyota not too long ago . Oh well that's a story for another day .

Good to hear brake booster motor working.

As I mentioned. Toyota very likely used bulk brake fluid. Some up-sell to BG super brake fluid. I've yet to see one use their Toyota brake fluid. So just top with what you have, if needed. Keep in mind. The level drops, as brake pads wear. So we don't actually need to full line, once they've worn.

Brake fluid flush, is more about time than miles. Although heavy use, like riding brakes. Does result in more heat. Which then miles do weight in more. Once factory fluid flushed out, which is best we'll ever have. We want to flush every 2 to 3 years.

Very cold start up squeal, with new pulleys/bearings. May just be a little belt slippage. But due keep ear tuned, and have checked if also after warm up.

 

[Mike NXP]

"that exact same" Which?


Good to hear brake booster motor working.

As I mentioned. Toyota very likely used bulk brake fluid. Some up-sell to BG super brake fluid. I've yet to see one use their Toyota brake fluid. So just top with what you have, if needed. Keep in mind. The level drops, as brake pads wear. So we don't actually need to full line, once they've worn.

Brake fluid flush, is more about time than miles. Although heavy use, like riding brakes. Does result in more heat. Which then miles do weight in more. Once factory fluid flushed out, which is best we'll ever have. We want to flush every 2 to 3 years.

Very cold start up squeal, with new pulleys/bearings. May just be a little belt slippage. But due keep ear tuned, and have checked if also after warm up.

Good call, probably put away a little wet ( snowing ) and then sat in super cold temps for a week. The noise did go away.

I've got the brake fluid all topped off properly and sitting at midway level. After the 40 pump deal the motor only ran for about 30 seconds maybe a bit more, and was intermittent at times. It sounded strong. Good to go for now but once it warms up the bigger question is; where did the fluid go? or maybe I was closer to the min line than I thought since I haven't really checked the level properly for a while.

 

[Eyedaho]

Good call, probably put away a little wet ( snowing ) and then sat in super cold temps for a week. The noise did go away.

I've got the brake fluid all topped off properly and sitting at midway level. After the 40 pump deal the motor only ran for about 30 seconds maybe a bit more, and was intermittent at times. It sounded strong. Good to go for now but once it warms up the bigger question is; where did the fluid go? or maybe I was closer to the min line than I thought since I haven't really checked the level properly for a while.

As @2001LC mentions, as your brake pads wear the brake pistons are pushed further out of the caliper bores. That extra space in the bores is filled with brake fluid, which drops the level in the reservoir. So after 30,000 miles you may have enough pad wear to drop the level. Of course it may have been underfilled or have a leak somewhere, but some drop in fluid level as the pads wear is part of the design of that system.