Brake Fluid

Chris,

Phil G answered a query on this a while back and I believe he said some of the Toyotas have a problem when dot 4 is used instead of dot 3.

If memory serves me correctly the dot 4 attacked the rubbers in the master or slave cylinders. I hope he sees this post and replies with the right information.

Have a good one,
RA.

I would be very interested in why Toyota would have a problem R.A. as all the research I have done shows that they are chemically the same with only a small amount or Borate added to Dot 4 to help raise the boiling point.
I would not have thought that Toyota would have brake hoses and cylinder rubbers especially made just for them.
Chris

Chris,
I don't know why but if you member message Phil I am sure he will let you know. I am pretty sure it was the 80 series but it is better to get it from the horses mouth.

His member name is Phil G (SA)

He seems to know Toyotas backward.

RA.

I had a problem in a 100 series when the mechanic replaced the brake fluid with Dot4 - the brake pedal almost immediately starting "sticking" - when I used the brakes the pedal didn't automatically come back up, and I had to often lift it with my foot under the pedal. I went back & had the fluid replaced with Dot3 (after reading on here I think:) & the problem went away. I also believe it was a problem with the Dot4 causing seals to swell. The car was a 2001 100 series petrol.

Yep, Doc is correct. The seals can swell when DOT 4 is used in Toyotas. That is why it clearly states on the caps, in the manual etc to only use DOT 3 in Toyotas. There was a warning put out by Toyota some years back - the problem seems most evident in the 100series with ABS.

Also, Toyota is not alone - all the Nissans I've owned have specified to only use DOT3 as well.

Rockape That,s exactly what the mechanic said a different Dot will attack all the rubber seals. He further stated your better off using water should you be low than a different Dot number just to get you home then ASAP flush the system.
Phil I went straight home and checked the Patrol cap it stated Dot 3 from a sealed tin only

Not to start an argument but I will challenge anyone to find any reference to where it says you cannot mix or use Dot 4 instead of Dot 3.
new boy, maybe your mechanic was thinking of mineral based brake fluids as these can cause your seals to swell but any of the ester based will not. someone correct me if they can prove that I am wrong.

Chris,
Unfortunately Exploroz has deleted all the photos I had stored on this site. So I've uploaded an article again here. I don't understand why anyone would consider anything except the specified DOT3.

Owned and maintained myself plenty of Motorbikes, Cars, and 4wd's over the years.

One thing I don't freelance on is the manufacturers recommendations for oils and fluids ..... if it says Dot3 - use Dot3 .... if Dot4 - use Dot4....

Thanks for Phil, I stand corrected, although my stubborn side says that the article does not give a definitive answer :)
Chris

Chris,

Not sure if you have a 100 series with ABS, but if so you are welcome to try it for yourself. I know what happened when mine had Dot4 put in, and it happened within a day or so. When it was flushed & changed back to Dot3, the problem went away within a few days. Coincidence? It's definitive enough for me.