Anyone have a close up picture of the vent/vane fin design on the large Toyota 4-Runner rotors? The FZJ80 Cruiser rotors I'm using have interesting internal fin design that looks like it may prevent warping better than traditional straight vane fin vent designs.

Has the brake booster push-rod adjustment been checked?

Jay

Richochet,

I totally agree about this brake deal. I've never had a car that had as many brake issues as my 4Runner. I bought the Toy to avoid this type of thing. I still love it, but, to be honest, it will probably affect my purchasing decision when it comes time to replace it.

Also, I noticed Jay chimed in about this problem. He is VERY knowledgeable about Toyotas. Don't take his advice lightly.

Mike

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by mhawker:
<strong>Richochet,

I totally agree about this brake deal. I've never had a car that had as many brake issues as my 4Runner. I bought the Toy to avoid this type of thing. I still love it, but, to be honest, it will probably affect my purchasing decision when it comes time to replace it.

Also, I noticed Jay chimed in about this problem. He is VERY knowledgeable about Toyotas. Don't take his advice lightly.

Mike</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">It is unfortunate that Toyota chose not to make the brakes a bit more stout on the 4Runner, or at least the 3rd Gens. One should not have to worry about getting the bigger brakes on 16" wheels, etc. It should be like on all my other older Toyotas and come with the stoutest brakes on the planet! And I actually did take a look at the push rod on the booster but I did not mess with any of that since my pedal travel is not out of line at all. The front brakes grab well with minimal pedal pressure, it is just those darn rear shoes that are not grabbing as they should. May be why the new 4th Gen Runner comes with four-wheel disc ?? <img border="0" title="" alt="[Wink]" src="images/icons/wink.gif" />

Anyhow, I did get under my truck and manually hit the adjusters a bit more and the braking is much better. Sad part is that the stealer just had this a short time back when I posted this thread so you wouldn't think the rears would be out already. The stealer probably did not adjust them as much as they could have. I usually run the adjuster up until I just start to get drag on the shoes with the vehicle rear axle supported on stands and with Tranny in neutral I spin the rear wheels free-hand.

But as Gadget pointed out I am going to start checking this at every oil change just to make sure. If it helps it is indeed worth the effort.

Ricochet

<small>[ December 24, 2002, 04:50 PM: Message edited by: Ricochet ]</small>

Dont waste your time turning the rotors. Once the rotors have been warped, they develop hot spots due to the extreme heat. The metallurgical changes that the rotors undergo during and after warping cannot be fixed by turning. You can turn the rotors over and over, but each time they are heated, their resistance to warping is diminished substantially. For example, once you bend a steel plate and straighten it out, the resistance to bending again is much less than before, in essence the metal becomes soft.

I would sincerely tell the dealer that unless they want you back every other day, just replace the rotors with new ones. If you are under warranty, tell them you will call the regional distributor or Toyota directly and complain. They will cave in. If not, then buy the rotors at autozone.

You probably know this, but breaking the rotors in is extremely important if you do not want them warped again. For the first 1000 miles, try to stop without trailing or Riding the brakes. Instead try to brake with steady but firm preassure on the pedal without "panic" braking. With new brakes (rotors and pads) you want "break in " the brakes by generating enough heat so that the pad material coats and transfers to the rotor, but not too hot where there is no transfer. I am not a mechanic, but have many friends who are mechanics at different dealerships and they allhave told me the same regarding brakes.
My 2 cents.!

Don't forget, when installing wheels the order of tighening the studs is amportant as the actual torque. I have seen many techs tighten lugs in a circle, which causes stress in the rotors.

Ideally, you should tighen every other lug and continue to work arount the wheel, torquing in two intermediate steps before reacing the final torque on the last pass.

And, despite what anyone says, an air wrench will not provide nearly as accurate a torque setting as a good torque wrench.

Just my $0.02 worth...

Brembo OE match rotors can be had for $46/rotor for 16" wheels, and $54/rotor for 15" wheels (dunno why 15" are cheaper) plus shipping (about $15) from Tirerack. Not too shabby, and comparable to the Aimcos from Autozone. Other options available elsewhere for cross-drilled, but the debate continues as to the advantages, if any, of cross-drilling...

How does one go about adjusting the rear brakes???

Thanks, Ryd

I got power slot slotted brembo rotors...excellent. I use Porterfield R4s carbon pads (pricey, but excellent). The nose-diving, I'd guess, is from too soft front springs/shocks. The stock suspension is really garbage...sags quickly, not progressive, etc. I don't turn my rotors. When you turn them, they're thinner and will soon warp again. Also, I spoke to wilwood about cross-drilled rotors. They advise against it, saying you lose 50% braking surface area vs. std rotors. The out-gassing really isn't a problem anymore, they say. It used to be w/ old organic pads. So I chosed slotted as a compromise...prevents the pads from getting glazed from hard braking, removes water from the rotors easier.

If I understand correctly the stealer has turned your rotors THREE times??? Its hard for me to believe that the rotors would still be within spec (too thin) even if the turnings were light. If possible, you should be there when they throw the mic on those puppies. I'll bet they are out of spec by now. If the stealer has replaced your rotors at some point then, as others have pointed out, you should keep an eye on the rear brake adjustment.

It has been my experience in the automotive world that once a rotor warps it should be tossed. Turning will provide a temporary fix but it will warp more easily since it is even thinner after turning. I've had excellent results turning rotors that were mildly scratched (but not causing shimmy) and reusing those. But never with warped rotors.