brakes

i have 2006 double cab prerunner trd sport, mine were really good for like 7 years, then got spongy, on the last replacement, i replaced wheel sensors, pads, rotors, and shoes. obviously got a little better because they were needing a change, but still spongy! next i am going to do is replace all the vaccuum lines, i think that maybe the problem. probably wont have the time for couple weeks, but i'll report back when i do it.

 

A leaking vacuum line would result in a loss of boost and you would notice the pedal getting harder, not softer. Id look at the soft lines at each wheel. they mihgt be getting soft from age. Or there is an air bubble and it needs the fluid bled more.

 

Try swapping out all of the fluid to DOT 4. Brake fluid absorbs a lot more water than what you think. I agree with checking the rubber lines too. I have braided lines all around, dot 4 fluid, drilled and slotted rotors with porterfield racing carbon kevlar pads, and a disk brake conversion in the rear and have zero complaints with braking performance, even with big heavy tires.

 

That's really quite affordable compared with going custom...

 

So someone is prolly gonna pick this post apart, but for what it's worth I'm just gonna say it. Upgrading rotors to cross drilled/slotted will have little to no effect on initial stopping power or day to day conditions. If anything it'll wear at your pads slightly faster, but not enough to really worry. Where drilled/slotted rotors come in handy is during racing or consistent hard braking where they are able to vent heat more efficiently and reduce fade. But, if that's your goal an even greater difference can be noticed by going to angled internal vein rotors, as opposed to straight vein or solid rotors. Not having done my brakes up front personally on my Tacoma, I'm assuming, and hoping, the Tacoma's are at least vented straight vein rotors. There's nothing wrong with running vented blank rotors. Upgrading to a better fluid like Motul 600 is a good option because they have higher boiling points. Stainless lines should, and in my experience will, firm up the pedal feel, and better pads can improve initial bite as well as long term fade.

 

No arguments, in fact I'm going to agree with you.

Slotted and drilled rotors actually REDUCE heat dissipation ability since they reduce the mass of the rotor. The purpose of the slots is actually to vent gasses that can be released by very aggressive track compound pads at extreme temperatures (Race cars can get the pads so hot they build up a bubble of gasses making the pad float). That's why you typically see them stock on high end European sportscars, especially with carbon ceramic rotors etc. The drilling actually weakens the rotor though which can be a liability in a road application say if you are braking hard, rotor heats up then you drive through a huge rain puddle - the rotor might not just warp it could crack around one of the holes/slots as those create stress concentrations.

For street use Ive always been told that drilled and slotted are mostly a waste of money. I have read there are benefits to cryo treated rotors (Centric and stoptech sell them among others), in that they wear better.


About the motul fluid - I used that in my Acura in the past, its good stuff. Its not going to change your feel in most daily driving though. As you mentioned its benefit is that it has a boiling point a good 100 degrees higher than street fluid so under constant heavily braking - like a mountain decent, multiple panic stops, or a track event, when stock fluid could get hot enough to boil the motul will still be good. But really if you are heating up your brakes that bad in street driving you might want to think about your driving habits

With everything there is a catch, and for Motul the catch is that it is more susceptible to moisture than regular dot 4 fluid. Motul reccomends yearly changes as opposed to the typical 3 years for street Dot3/Dot4. I left some in my car once for two years and it turned dark brown. YMMV but Id watch it.

 

Put one stock rotor on and one slotted rotor on the other side. Go splash through a mud puddle and slam on the brakes. I bet it pulls to one side. I like them for wet weather/offroad use, seems to get extra bite. The cheese grater effect may be true, but one thing is for sure, I don't have glazed pads! Buy what makes you happy.

 

username and charlie g, thanks for the tips, i will try asap!

 

I'm into my third 2nd generation Tacoma ... the '06 and '10 had the spungey (is that a real word?) pedal/brakes. I expected the same when I picked up my '14 Prerunner Off Road ... they do not respond as the previous did ... no issues ... quite pleased.