myblue91

finally going to replace the rear rotors(very very warped) and pads on my 91. Have been told I'll have to disable the parking brake automatic adjuster because the caliper will have to come off...is this a difficut job to do??? Who out there has done this before,any suggestions

bogus

don't fuss it... remove the caliper and the bracket... real easy.

ittlfly

Just remove the 2 bracket to backing plate mounting bolts and lay the assembly aside. You can pull the rotor off then and not disturb the caliper.

myblue91

So that adjuster is not a problem? Can I reuse the bolts?

ittlfly

Yes, you don't have to fool around with the adjuster if you remove the whole unit as suggested. You can resuse the OEM bolts with a little lockite on the threads. However, the General suggests that you replace them (at appx. $5. per bolt) Your call.


[Modified by ittlfly, 7:28 PM 7/3/2004]

myblue91

Thanks guys, did the fronts some time ago and they were "easy' so I was hoping for the same in the back

bogus

You will probably need a c-clamp or something like that so you can compress the piston back.

As a side note, brake rotors don't "warp". The iron is too thick to be effected by even high trancient tempatures.

What happens is that brake pad material transfers to the surface of the rotor, adding buildup. The end result is a rotor out of parallel.

88vettelover

Rotors are made of steel, not iron, and are very prone to warping, especially since the steel used on brake rotors is cheap.

Brake pad material is not added to the surface of the rotor. I don't know where you heard that. Rotors become warped from high heat or from being to thin. Some brake systems heat up in very high temperatures. With hard pads, semi-metallics, these eat away at the rotors. When people just slap pads on them, it continues to eat away at the rotor (metal on metal) and eventually they become thinner and more susceptible to heat. This heat causes warping of the rotor itself.

This is why it is necessary to replace/resurface rotors when changing pads. You need a flat smooth surface for the pad to break-in on. Without this, the pad forms to the unsurface rotor and continues in the imperfect pattern. Over time, again, warping occurs.

rons85

mitchcole

Yup - rotors warp. I had that happen on my honda. Every time America's Tire would torque the rims on - pototo chip discs. I don't let them near my car. I'll buy their tires - but I just take the rims over in the truck.

bogus

If you all don't beleive me, beleive the late Carroll Smith, legend of motorsports. He worked with Shelby in the 60s and most recently, with Stoptech brakes:
http://www.stoptech.com/whitepapers/...otors_myth.htm

Very informative.

dlmeyers

Ive seen that article before.

Keep in mind the givens. Proper hardware, proper torque sequence, etc. This assumes all wheel geometry is correct. Do you think every shop in America follows the proper procedure. I would not rule out anything when dealing with a pulsating pedal. Shaving a few thousands off with a twin cut lathe (lathe cuts both sides with one pass) usually does the trick. This saves "flipping" the rotor. Proper "bedding in" and good torque wrench does wonders. 3M makes some nice sanding disks although I've never researched their content. I assume they're up to par.

Depending on the disk, design, heat spots, webbing, etc, some can be cleaned up quite nicely and do not require replacement. This assumes a non race application, normal street driving.

Still, nice article.

Now, back to your regular programming.

dlmeyers 90 coupe zf6 3 speed shocks


[Modified by dlmeyers, 11:30 AM 7/5/2004]

bogus

I have my own empirical data, too. I have cut my share of rotors on a brake lathe, and more times than not, the high spot does not corrispond with a low spot. If it had warped, I would expect the warp to follow.

As for Honda rotors, yes, they were junk and prone to wheel torque problems...