Wearing out rotors.

[awguthrie]

My 91 Bronco, 300 ci, auto, 3" susp lift, has worn out the outer portion of the left rotor. This is the second time. The wear on the rest of the brakes seems minimal. The inner pad is worn, yet the outer pad was ok. I'm obviously missing something. :blink:

 

[miesk5]

My 91 Bronco, 300 ci, auto, 3" susp lift, has worn out the outer portion of the left rotor. This is the second time. The wear on the rest of the brakes seems minimal. The inner pad is worn, yet the outer pad was ok. I'm obviously missing something. :blink:

yo! following excerpts are from links in my web site; from Tomken, etc. GL! eziest ck is lug nut torque...who did the jobs?..and what did they say they used for torque; should be 100 ft-lbs

Wheel Lug Nuts, Over-tightened and/or Unevenly Torqued - Preventing Brake Vibration Tip Rev TSB 98-5A-4 for 79-96 Source: by Ford via miesk5

"ISSUE: The use of air impact tools to tighten wheel lug nuts can lead to overtightened and/or unevenly tightened wheel lug nuts. Air impact tools typically used for wheel lug nut removal and installation can generate up to 475 N-m (350 lb-ft) of torque. Overtightened and/or unevenly torqued wheel lug nuts may cause:

- Brake vibration

- Distortion of the wheel hub

- Distortion of the brake rotor

- Brake rotor runout

- Damage to the wheel

- Damage to the wheel nuts and studs

ACTION: All wheel lug nuts should only be tightened to specification using a torque wrench or by using the Rotunda ACCUTORQ 164-R0314 or equivalent on a 1/2" drive air impact tool. The "ACCUTORQ" lug nut sockets limit the torque of the air impact tool, preventing overtightening or uneven tightening of the wheel lug nuts. The torque limiting devices (regulators) on air impact tools will not reduce the output torque enough to prevent overtightening of the wheel lug nuts.

NOTE: REFER TO THE APPROPRIATE SERVICE MANUAL OR THE CHART IN

 

[madmax]

"quality rotors and drums are better metallurgically as well as dimensionally. The alloys used in quality castings tend to be more stable and consistent, which reduces the risk of hard spots and uneven wear developing over time."

Don't bother with the imported rotors from auto zone, they tend to wear very quickly and they always have to be re ground before installation. Get American or Canadian made rotors from NAPA or FORD or high performance rotors from bronco graveyard. Also unless you get fancy cross drilled and slotted rotors, stay away from ceramic brake pads, they make less dust because they are harder, this causes them to cut into the rotor faster, instead get decent regular brake pads or semi metallics. I'm looking around to see where I can get asbestos brake pads and clutch disks cause they almost never **** rotors or pressure plates and they just seem to work better in general. The only problem is you have to wear a respirator when you work on the brakes, something you should do anyway.

 

[snowman74]

Has anybody used those pads from summitracing.com called green stuff, or something like that? Just curious. I'm about to put new rotors, calipers, pads, bearing job, etc. on the front of my 87...and I was thinking about using cross drilled rotors because of high heat (lots of highway use). Any suggestions.

Al always provides the best info...I wouldn't have thought of improperly set-up lathes. I'd be curious to find out if it was the bearings, the calipers or the rotor machining.

Snowman74 >-