Hilux Brakes

[Steve9R]

Surfseeker ... Question for you then..

have you bled the Proportionary valve ? (it needs to be bled first)..

the symptoms you are talking about are definately going to be air in the lines somewhere..

you're meant to bleed in the correct order too.. APV first, then (edit:) LHR RHR LHF RHF (as max correctly said below )..

i just had all my brake lines off over the last week, and has a mystery bubble of air causing the same issue.. but doing it in order got it out..

Steve

[Hilux Max]

steve, you got the order wrong mate.....

The brake fluid reservoir is on the LHF side of the vehicle (drivers) and you start bleeding at the furthest point first which would be LHR, then RHR, the LHF then RHF.

[Surfseeker]

Max and Steve,
This may indeed be the problem
So do I start by bleeding the load valve?
To be honest I am not certain that the valve was actually bled as I was the one in the car pressing the pedal while the brake guys did their thing....
I am more suspicious that this might be the issue as we did replace the flexible rear line at the same time and from memory the load valve sits above this line....

So can I firstly check that the load valve does need to be bled and secondly that if it needs to be done first.

You guys seem to know much more about this than me and I would love to get this resolved.

Cheers

Scott

[Steve9R]

steve, you got the order wrong mate.....

The brake fluid reservoir is on the LHF side of the vehicle (drivers) and you start bleeding at the furthest point first which would be LHR, then RHR, the LHF then RHF.

ahh crap i have too i always stuff up the LH RH as it depends on which way im looking at the vehicle.... thanks max !

Max and Steve,
This may indeed be the problem
So do I start by bleeding the load valve?
To be honest I am not certain that the valve was actually bled as I was the one in the car pressing the pedal while the brake guys did their thing....
I am more suspicious that this might be the issue as we did replace the flexible rear line at the same time and from memory the load valve sits above this line....

So can I firstly check that the load valve does need to be bled and secondly that if it needs to be done first.

Yes Load Valve sits up under the tub and has to be done first.. then LHR RHR LHF RHF (as max said )..

Steve

[Surfseeker]

OK.....I checked and the Load valve and all other wheels were bled properly first up.
Did it again just in case.
Definately no air in the system and I still have the problem.
In any case as air is compressable and brake fluid is not, air in the lines would feel spongey but consistant, where as I have a firm but inconsistant pedal.
I have a Good pedal one minute then the pedal just sink and goes away from you. One pump and back to normal.
If you keep constant pressure on it it sinks slowly (takes about 15 seconds)to the floor.
It feels just as if you are getting a pypass at the master cylinder...except that shouldn't be happening as:
1. it was almost new when we started.
and
2. we put a seal kit through iit and pressure tested it just in case!

I am at the point where I feel I need to remove the brake rotors and calipers and refit the originals to see if the brakes return to normal. Even the brake experts are stumped by this and do not believe that anything we have done should have caused the issues that we currently have. They also don't see that returning to OEM spec will help but what else can I possibly try?

[Steve9R]

the symptoms you are stating are still indicative of air in the lines.. even though you say its a firm feeling, holding your foot on the pedal and it slowly dropping to the floor is definately air..

one pump and back to normal = air..

i dont know what to say mate.. but to me there's an air pocket somewhere that isnt clearing.. maybe it is in the rotors you put on ? try changing them but i think its unlikely..

Steve

[Surfseeker]

OK Guys, I may finally have solved the gremlin in my braking system and there is possibly a lesson in this for anyone else considering the TRD / Prado brake upgrade as perhaps I am the one responsible for my own problem.
If you read further up this post you will see I have been suffering with a brake pedal which is fine one minute and then "dissappears" the next time you apply the brakes.
We have been baffled by this and have put the problem down to many things, none of which turned out to be correct.
So without further fanfare the answer was.....not the braking system at all but bloody wheel bearings!!!!
How so?
If your wheel bearings are not within spec it allows a degree of movement in your wheels as they rotate. This in turn can cause the rotor to push agaisnt the pads and in turn push the pistons back into calipers. Next time you apply the brakes it takes one pump to get the pistons to effecively reposition the pads where they should be, then another to start stopping the car!!!
Bloody hell, this stuff is difficult sometimes...If you have a brake problem then check the wheel bearings!!!
The reason I am writing this is because I think I may in fact be the one responsible for my "wobbly" wheels.
When I did this upgrade there were two ways to go about it. One way was to bend the existing dust shields back to accomodate the bigger rotors and calipers. The other was to fit the TRD/Prado dust shields. Being a sucker for punishment I decided to install the bigger dust shields. This turned out to be by far the most difficult part of the whole thing as it required the removal of the hub assembly. I now believe that when I reassembled this I did not do it correctly which has caused this problem has taken us months to diagnose.

So the moral of the story is....if you do this conversion, unless you are mechanically proficient (I thought I was good with a spanner but have just been proved wrong!!!) then just bend the existing dust shields and don't bother putting on the TRD / Prado ones. It is just too much trouble for too little benefit and has the potential to go a bit pear shaped. So just bend the existing ones to suit, If you do that then the whole conversion could be done in less than an hour as it is just bolt off the old ones bolt on the new then bleed it up and away you go.
Hopefully this helps someone not to make the same mistake .....
Its almost all finished but once I get it finished tomorrow I will report on my "new " brakes

[KTM525EXC]

Ive never heard of that b4 Scott, I wonder if warped rotors could create the same problem??? I'm glad you got it sorted

Cheers Troy

[Surfseeker]

Troy,
We thought of many things that might be responsible but wheel bearings were not one of them.

Yep...warped rotors would do the same thing i suppose....

Now if only I can get my bloody fuel gauge working!!!!

[Downunderlux]

Thanks for the insight to your problem. Hope the new brakes in the end provide much more relief to getting the car stoppping.

[Surfseeker]

Finally.....
I have brakes that work properly!
The pedal is now much better (and higher) than before and, thank god, I now know what i am going to get when i press the brake pedal.
Just to make my day a little better I had occasion today to drive one of the new updated trucks with the 17inch wheels.
My car is now clearly heaps better in the braking department. I have a better pedal feel and tons more braking power. So finally the TRD/Prado brake conversion is showing its true potential and i can now say it is certainly a worthwhile mod.
As I mentioned yesterday just don't get carried away and bite off too much. Doing the dust shields is too hard and means clearly introduces a whole other set af things you can stuff up along the way.
Just bend the buggers and avoid the drama.

[Philby]

The trick I used when I did this conversion was to mark the position of the nut with a permanent marker. This guaranteed the correct preload was applied to the bearings on reassembly.

[H20PRF]

And if anyone read on the News today, TOYOTA is about to recall 30 thousand , yes 30 thousand vehicles in OZ due to crap yes crap brakes, no info on what vehicles as yet

[Jack S]

And if anyone read on the News today, TOYOTA is about to recall 30 thousand , yes 30 thousand vehicles in OZ due to crap yes crap brakes, no info on what vehicles as yet

I heard it was to do with a brake fluid leak issue...

[Hilux Max]

Your right Jack....its not to do with crap brakes on hiluxs in general...supposedly the brake booster on some vehicles is leaking fluid.

[IFS-LUX]

[quote="Surfseeker"]G'Day Guys,
A penny for your thoughts.....
If you have read this thread you will know that I completed the Prado brake upgrade.
Since the day the new brakes were fitted I have not been entirely happy with the result.
The problem is the pedal feel. I wrongly described this as a "Spongey" pedal leading to the conclusion that the problem was incorrect bleeding (air in the lines). With the benefit of hindsight I should have described the problem as an Ïnconsistant" .....

Check your wheel bearings they maybe pushing your pistons back in i had that problem with my older hilux

Assuming you removed the hub to change the rotor and the bearing set up is similar


EDIT hahaha pays to read to the end of a thread before posting, has to be one of the most frustrating problem i have ever had with my hilux and it was all self inflicted and no one thought it may be the cause of my problems

[jogal]

As much as i would of liked to do the Prado upgrade the cost of new rims and tyres was just to much and after researching this option with keeping the 16" wheels i didnt want to start grinding the calipers, so i ended up getting my disc's machined put in braided brake lines and a set of Lucus performance pads in. It wasn't that cheap i thought for $750 but the improvement is definately felt, it actually stops now.
In terms of the legality's about the Prado upgrade my Toyota dealer was going to fit the upgrade with me providing the parts with no change to my factory warranty.
So my conclusional would be if your running 17" or bigger wheels go the Prado upgrade if not what i have done definately works as well.

[Carp]

i thought there must be something wrong with mine but they are just crap

[leggy]

does everyones poor brake performance include, when you go to get on them hard and fast they grab,give way,grab,give way,sort of like a shudder feel under your foot..?????

[johnny5x]

does everyones poor brake performance include, when you go to get on them hard and fast they grab,give way,grab,give way,sort of like a shudder feel under your foot..?????

That will be your ABS