On Sun, 08 Dec 2013 14:52:09 -0600, Leon lcb11211@swbelldotnet
wrote:

On 12/8/2013 12:54 PM, wrote:
On Sat, 07 Dec 2013 23:49:53 -0600, Leon lcb11211@swbelldotnet
wrote:

On 12/7/2013 8:13 PM, Larry Blanchard wrote:
On Sat, 07 Dec 2013 14:50:42 -0500, woodchucker wrote:

I just replaced them last year, rotor and pads. You can't find anyone to
resurface rotors anymore.

My mechanic tells me that the rotors are made so thin nowadays
(supposedly to save weight) that it's not safe to turn them down.



Many rotors are a composite material vs. solid steel. You turn them you
ruin them.
Many???????
Extremely few production brake rotors are anything other than cast
iron or cast steel.. Most of the damage done to rotors is due to
chemical reaction with metallic compounds in the prake pads,
compounded by road salt. All rotors have a "service limit" and a
"machining limit". Used to be they were significantly different and
you could cut a rotor up to 3 times. With the advent of CAFE, and the
resulting weight reduction "imposed" on manufacturers, brakes are
often now undersized for the application, and so low in mass that they
cannot handle extreme heat - and machining them reduces the mass to
the point the quickly warp after being machined. With today's labour
cpsts, and the cost of 3C parts, it is cheaper to replace than to
machine MOST brake rotors.
Good brake pads today are VERY expensive compared to rotors - It is
false economy to buy the cheapest rotor you can buy unless you are
also putting on the cheapest pad you can buy and are not planning on
keeping the vehicle roadworthy for any length of time.

My modus operendi is to never buy either the cheapest or most
expensive part unless there are only 2 or less options.


Yes, many. Many is not a specific number or ratio to all as a whole.
Plenty more than pre 90's
What normal production non-specialty vehicle uses composite rotors.
Name 3 - 2 of which must be generally available for under $60,000 US