dot 3 or dot 4??

[tulula]

Hey fellas did a quick search but could not the life of me find any info so here goes.
Brake fluid on our res caps suggests dot 3 only. I am currently running dot 4 or super dot 4 as on the bottle it states that it can be used with the application of dot 3, dot 4, and dot 5.1. A mate of mine warned me that only with toyota does this not! Apply. Apparently it must be dot 3 else it may damage the internal seals. Can anyone shed some light on this matter would greatly appreciate it.

[Jack S]

The only difference is the the boil point temp. dot 4 has a higher boiling point that dot 3, so using the higher dot in the hilux wont matter, but if it makes you feel better and safer than by all means use dot 3...
DO NOT USE dot 5 as this is a synethic oil and totally different to dot 3 & 4!!

[tulula]

Thanx jack. Yeah aware of dot 5 is a no go zone. Only reason y i asked this is cus this mate was workn for an automotive shop, and they had to relearn some product knowledge and apparantly this happened to a dudes toyota, used dot 4, blew his seals and went thru a claim of somesort advising it stated on the packaging it was ok to. Dude got fully refunded and his seals fixed under claim.

[BIGFOOTJR]

I use vegetable oil in mine..

[hilder91]

yer use dot 4. dot 4 has a higher boiling temp than dot 3 and will not absorb as much water than dot 3. u can use dot 5 it has a higher boiling point compared to 3 and 4 but the whole brake system has to have a full flush other wise the break fluid will damage the seals. dot 5 last longer and has a more stable viscosity index over a wider range of temperatures. and it is expensive

[StevenS]

Everyone should be aware there is a difference between a Dot 5 and Dot 5.1 fluids.

Dot 5 should only ever be run in a system designed for and only ever having run Dot 5, as it is silicone based not poly-glycol based like Dots 3,4 and 5.1

Dot 5.1 is compatible with Dot 3 and Dot 4 fluids and is safe to use in these systems. You can also get super dot 4 which superior to dot 5.1 .

[StevenS]

Also you definitely should not run Dot 5 in a system not designed for it, even if you do a "full flush". Dot 5 fluids require the braking system be specifically developed to run it and it requires special seals and other parts more resistant to corrosion .
As it is silicon based, water won't mix with it as it does with poly-glycol compounds which can result in water being trapped in the system and able to corrode parts