Coustic

I have been wondering for some time now, is there a difference between 2001-03 braking systems and 2004-06 braking systems?

I know that they both use the same pads and rotors but there is a difference in feel.
Little back story: I drove my dad's 2004 which has nice firm braking, but then i drive my 2002 or even my brother's 2001 and it has a sort of squishyness to them.
The 2004 and 2001 both have the exact same pads and rotors, we changed all pads and rotors weeks apart from each other, we even flushed both systems with new fluid.

They still have a feel difference. Know my question to y'all is: Is there a difference between 2001-03 brakes and 2004-06? or is something wrong with the 01-03s?

airchomper

I've never had the privilege of driving an '04-'06 but my 01's brakes used to be not so good. I don't know if their braking components are different but I doubt Toyota changed it during the facelift.

Getting fresh DOT4 braking fluid in my car and bleeding the air out of the system made a big difference. Squishiness in the pedal is a symptom of air in lines, have it checked out next time you're in the shop.

XJSFan

I think these brakes call for Dot 3 brake fluid.

Tom57

Lexus uses Dot 4 Brake fluid - higher boiling point reduces likelihood of air bubbles under normal driving conditions.

Coustic

Huh, i used DOT3 fluid, the cap says to use it...
I have had the brakes flushed and did them my self before.
So far no difference

Tom57

Well, that's great you've experienced no difference - "so far." Dot 3 brake fluid is the minimum Department of Transportation standard for brake fluid. Since that "Dot 3" brake fluid reservoir cap was installed, Dot 3 brake fluid has largely been replaced with the superior qualities of Dot 4 fluid. Dot 3 and Dot 4 are comparably priced as well. With the enhanced protection afforded by Dot 4 fluid, why would you not be certain to use it, especially in the most important function in a car, your brakes?

XJSFan

The 06 LS 430 is specd using DOT 3 brake fluid. Not sure if you know, but many manufacturers still spec DOT 3... This is not a case where which one is better but which fluid is specd for the LS 430 application. Dot 4 and 5, which are not compatible(with each other), are for higher heat applications which are for performance/racing applications. My Jaguar V12 specs Dot 4 because of the under hood heat issues. The Lexus LS 430 does not have this problem. Go to "bob is the oil guy" forum and you will find a lot of good/accurate info on most automotive fluids.

Tom57

Have an '06 and '01 - know what they're spec'd for; read the "oil guy" before. Dot 4 is a higher rated spec than Dot 3 - see post # 4 - has a higher boiling point. If brake fluid boils, it turns to gas, which is compressible and the braking system becomes “spongy” or in extreme cases fails completely. Brake systems are not perfectly sealed - moisture can get into the system and be absorbed by the fluid. The effect is to reduce the boiling point of the fluid, which reduces the effectiveness of the braking system leading to longer stop distances. With its higher boiling point, Dot 4 provides a higher margin of safety even for passenger vehicles with extensive stop-and-go, driving hilly or mountainous terrain, etc. Dot 4 is fully compatible with Dot 3 spec'd cars, but not the reverse.

The V12 requires Dot 4 because the vehicle may be driven at high speeds requiring heavy use of brakes - the calipers and rotor get so hot and the heat transfers to the brake lines and brake fluid at the calipers. Under hood heat doesn't come close to the extreme temps at the calipers after heavy use.

This discussion should serve as a reminder to flush the brake fluid at regular intervals even if the brakes "feel" fine. Moisture eventually gets into the brake fluid.

XJSFan

I know about brake fluid... LOL. I just believe that most people here would be better served using the spec fluid.

Tom, you are 100% correct with flushing brake fluid at regular intervals.. I would bet most people do not do this.

Tom57

Valvoline offers brake fluid that is DOT 3 & 4 compatible. DOT 4 brake fluid is compatible with DOT 3 spec vehicles since it not only meets but it exceeds the specs of DOT 3.

XJSFan

I have used Valvoline 3/4 fluid and it seems to do the job...

GSteg

iTrader: (15)

One thing to note that the part number for the master cylinder changed. Whether the changes were made for performance or not, who knows. There could be other things that changed but I haven't looked into it.

Coustic

Thats probably what it is...
Now to see if the 2 are compatible with each other.

Kira X

iTrader: (24)

My 05 LS' brakes seem to feel better than my 02's brakes.