bitpoop

i have a stock 1991 toyota 4runner with 100k miles.
i have upgraded the front pads with hawk super duty pads,
rebuilt the front calipers new rotors and put on a new master cylinder from ray b.
i had to replace the rear portioning valve as it was not working.
the truck seems to stop ok for daly trips but when on the freeway in a emergency stops the brakes don't work good for the first 100 feet then they grab at the last second. they don't seem to bit until they get hot witch takes like 100 feet?
i once installed green stuff pads on my truck to only remove them the next day as they did not stop the truck, vary dangerous.
thats when i looked for the most biting brake pads and found hawk super duty pads. i forgot how the stock pads performed so i am posting on this forum.
everything in the brake system seems good? is there an upgrade i can do by using newer t100 brakes or something?
are the stock brakes that bad on a 1991 4runner? or is it just my truck?

scope103

I can lock up the brakes, even with a moderate load in back. I don't drive REAL fast, but I'm pretty sure it's your brakes rather than a 4runner generally.

Are you sure the brakes were adequately bled? A "spongy" brake is the usual description for when you have air in the system.

bitpoop

this is a 1991 4runner with anti lock rear brakes.
is your truck the same?
the only thing i have not done is to check the psi at the front calipers.
i don't have that tool, but i think they are fine as it brakes even.
the pedal is hard and it does not drop, when u press hard the pedal only
goes down like an inch at that point u are at max braking, i used two feet before trying to stop. when i went from green stuff to hawk brake pads that improved my brakes 10x. so i feel safe but trying to stop from 70 mph reminds me of my 1970 vw bug. for the first 100 feet then it bites hard.
i am waiting for a reply from hawk.
next ill re bed the brake pads and see if that helps.
i am confused because i don't believe green stuff would sell brake pads that don't stop your car, when i had them on the truck would not stop it was like i only had back brakes. that made me get a new master cylinder but that did not help.
then i rebuilt the calipers and that did not help, then i got hawk super duty pads because they have the most friction and they bite hard and it helped a ˟˟˟˟load but not on emergency stops for the first 100 feet. i have the green stuff pads if anyone with my same truck wants them to test? ill send them to u.

thook

My experience with 4rnr brakes is with a heavy trailer and living in the Ozarks. Both the 1st and 2nd gen have always stopped very well even on the highway. Now, I don't go 70mph with a trailer nor do I even do 70 unloaded, really. Just the same, I never have problems stopping. And, I use O'Reilly pads.

So, you never mentioned the condition of the rear brakes. Have you had a look at them?

wyoming9

iTrader: (1)

These are heavy vehicles They are not sports cars..

When you rebuilt your calipers what grit stones where on your hone?? Poorly honed bores can also cause problems slowing piston travel down .

Are you using the emergency brake to keep the rear brakes adjusted ??

New rear shoes and drums ??

Have all the rubber hoses been replaced ?? Ballooning hoses are a real cause for degraded brake performance .

Because the hose swells up before fluid is acting on the calipers or wheel cylinders.

The brakes are a complete system the whole system needs to work together.

I have never had problems stopping but I adjust my following distance according to conditions .

RJR

I agree with the other posters, that normally the stock brakes on a 4runner are quite good. If you're having trouble stopping, something is wrong.

I haven't quite been able to follow which brake pads you've been using and which are troublesome, but one thing I would start with is going back to OEM pads. Generally after-market "super duty" pads are oriented toward long life. They get that long life by making them of harder materials which have less friction against the rotors and thus don't stop as well. In general, with brake pads, at a given price point life and stopping effectiveness are inversely related. You maximize one by sacrificing the other.