Brake rotors already grooving

> > > >Did you happen to have the rotors cut or resurfaced? i.e. happens
> to be a
> > > >requirement when replacing a rotor!
> > >
> > > Foo!
> >
> > same to you pal!
> >
> > > Where did you get that nonsense!
> >
> > I don't know what where you come from! Here in the US most NITB
> rotors will
> > require a base cut before installation
>
> What are NITB rotors?



LOL >> NITB = "New In The Box"



>Who told you that new rotors needed a "base cut"



Common sense tells me - plus, raw hands on experience = knowledge!!!


> As with the others here, I've never heard of such a thing.



.....Possibly the next time you have someone do a brake job. Why not ask one of
the ASE certified techs! Or you could drop by your local machine shop - shoot
the **** with the machinist..



BBA

On Wed, 12 Jan 2005 19:44:21 -0800, "BBA"
> wrote:

>> > > >Did you happen to have the rotors cut or resurfaced? i.e. happens
>> to be a
>> > > >requirement when replacing a rotor!
>> > >
>> > > Foo!
>> >
>> > same to you pal!
>> >
>> > > Where did you get that nonsense!
>> >
>> > I don't know what where you come from! Here in the US most NITB
>> rotors will
>> > require a base cut before installation
>>
>> What are NITB rotors?
>
>
>
>LOL >> NITB = "New In The Box"
>
>
>
>>Who told you that new rotors needed a "base cut"
>
>
>
>Common sense tells me - plus, raw hands on experience = knowledge!!!

I'm sorry to have to report, that in YOUR case, common sense plus raw
hands on experience = NITWICITY

To the point:
http://www.procutinternational.com/h...gm_review.html
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

Original equipment rotor surfaces are ground to ensure smooth finish
and parallelism between mounting and friction surfaces. New rotors
SHOULD NOT be resurfaced before installation. When rotor turning is
necessary, it is essential that you use a high quality brake lathe.
Rotors, when remounted on the hub, should have less than 0.080 mm
(0.003 in) lateral runout. Brake rotors should only be turned when one
of the following rotor surface conditions exist:

1. Severe scoring - depth in excess of 1.5 mm (0.060 in).

2. Pulsation concerns from:

* Lateral runout in excess of 0.080mm (0.003 in).
* Thickness variation in excess of 0.025 mm (0.001 in).
* Excessive corrosion on rotor braking surfaces.

Rotors are not to be resurfaced in an attempt to correct the following
conditions:

Noise/squeal
Cosmetic corrosion
Routine pad replacement
Discoloration/hard spots
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

I really dislike shooting ducks in a barrel, there is no *sport* in
it.

Try to do better next time. Make it a little more exciting.

Lg

In article >,
Lawrence Glickman > wrote:

> On Wed, 12 Jan 2005 19:44:21 -0800, "BBA"
> > wrote:
>
> >> > > >Did you happen to have the rotors cut or resurfaced? i.e. happens
> >> to be a
> >> > > >requirement when replacing a rotor!
> >> > >
> >> > > Foo!
> >> >
> >> > same to you pal!
> >> >
> >> > > Where did you get that nonsense!
> >> >
> >> > I don't know what where you come from! Here in the US most NITB
> >> rotors will
> >> > require a base cut before installation
> >>
> >> What are NITB rotors?
> >
> >
> >
> >LOL >> NITB = "New In The Box"
> >
> >
> >
> >>Who told you that new rotors needed a "base cut"
> >
> >
> >
> >Common sense tells me - plus, raw hands on experience = knowledge!!!
>
> I'm sorry to have to report, that in YOUR case, common sense plus raw
> hands on experience = NITWICITY
>
> To the point:
> http://www.procutinternational.com/h...gm_review.html
> //////////////////////////////////////////////////////////////////////////////
> ////////////////////////////////////////////////////
>
> Original equipment rotor surfaces are ground to ensure smooth finish
> and parallelism between mounting and friction surfaces. New rotors
> SHOULD NOT be resurfaced before installation. When rotor turning is
> necessary, it is essential that you use a high quality brake lathe.
> Rotors, when remounted on the hub, should have less than 0.080 mm
> (0.003 in) lateral runout. Brake rotors should only be turned when one
> of the following rotor surface conditions exist:
>
> 1. Severe scoring - depth in excess of 1.5 mm (0.060 in).
>
> 2. Pulsation concerns from:
>
> * Lateral runout in excess of 0.080mm (0.003 in).
> * Thickness variation in excess of 0.025 mm (0.001 in).
> * Excessive corrosion on rotor braking surfaces.
>
> Rotors are not to be resurfaced in an attempt to correct the following
> conditions:
>
> Noise/squeal
> Cosmetic corrosion
> Routine pad replacement
> Discoloration/hard spots
> //////////////////////////////////////////////////////////////////////////////
> //////////////////////////////////////////////////////
>
> I really dislike shooting ducks in a barrel, there is no *sport* in
> it.
>
> Try to do better next time. Make it a little more exciting.
>
> Lg

Careful there Lawerence, you're going to kill billybadmechanic's
cash cow.

On Wed, 12 Jan 2005 15:22:02 -0800, John Ings >
wrote:

>On Wed, 12 Jan 2005 14:37:12 -0800, "BBA"
> wrote:
>
>>> >Did you happen to have the rotors cut or resurfaced? i.e. happens to be a
>>> >requirement when replacing a rotor!
>>>
>>> Foo!
>>
>>same to you pal!
>>
>>> Where did you get that nonsense!
>>
>>I don't know what where you come from! Here in the US most NITB rotors will
>>require a base cut before installation
>
>To the dertiment of the customer's wallet and the benefit of the
>mechanic's bottom line!

Brake rotors (and drums) all tend to warp as the casting ages.
They also get a lot of abuse in handling. The machining of hubs and
mounting surfaces may be true to the friction surfaces when they're
made at the factory, but after shipping, stocking, and even just
months on the shelf, it's a different story. Some are worse than
others, but they ALL need to be surfaced before installation. Anyone
with experience on a brake lathe is aware of this, as is anyone with
formal training in automotive technology.

LMAO >>> Maybe you should consider actually reading the page before posting i.e:
this is a GM Service Bulletin!!!!! I take it you don't actually know what it is
that you are talking about!!! not a question >> is a matter of fact!!!

Here's what it really says:

General Motors

Service Bulletin
Warranty Administration
File In Section: 05 - Brakes
Bulletin No.: 00-05-22-002
Date: February, 2000
Brake Rotor Warranty Service Procedure
Models: 1995-2000 Passenger Cars and Light Duty Trucks

"GM highly recommends the use of on-car brake rotor turning as a method of
eliminating the stack up of lateral runout which is a potential source of brake
pulsation. GM has identified superior equipment through testing and evaluation.
The *Pro-Cut PFM900 will consistently deliver machined rotors that meet GM
specifications (lateral runout less than 0.080 mm (0.003 in) and is the only
on-car brake lathe that is currently recommended by GM..."




This bulletin outlines GM's standard procedures and guidelines for brake rotor
service and brake wear.
Important: Certain conditions may apply to individual vehicles regarding
specific repairs which differ from those outlined in this bulletin. Refer to
those specific repairs in applicable bulletins.
Original equipment rotor surfaces are ground to ensure smooth finish and
parallelism between mounting and friction surfaces. New rotors SHOULD NOT be
resurfaced before installation. When rotor turning is necessary, it is essential
that you use a high quality brake lathe. Rotors, when remounted on the hub,
should have less than 0.080 mm (0.003 in) lateral runout. Brake rotors should
only be turned when one of the following rotor surface conditions exist:
1. Severe scoring - depth in excess of 1.5 mm (0.060 in).
2. Pulsation concerns from:
* Lateral runout in excess of 0.080mm (0.003 in).
* Thickness variation in excess of 0.025 mm (0.001 in).
* Excessive corrosion on rotor braking surfaces.
Rotors are not to be resurfaced in an attempt to correct the following
conditions:
Noise/squeal
Cosmetic corrosion
Routine pad replacement
Discoloration/hard spots
Explanation of Brake Rotor Warranty Service Procedure
Rotor refacing during normal pad replacement is not necessary.
Rotor refacing for cosmetic corrosion is unnecessary. Clean up of braking
surfaces can be accomplished by 10-15 moderate stops from 62-75 km/h (35-40 mph)
with cooling time between stops.
Rotor service is ineffective in correcting brake squeal and/or premature lining
wear out and should not be used to address these conditions unless specifically
directed by a service bulletin.
When installing new rotors, DO NOT reface them. If a new rotor has more than
0.080 mm (0.003 in) lateral runout when properly mounted on the hub, it may be
machined using an approved on-car lathe. Ensure bearing flanges and rotor
mounting surfaces are free of corrosion when installing rotors to prevent
inducing lateral runout. Use Kent Moore tool J-42450A to clean the corrosion
around the wheel studs.
Always mark the position of the rotor on the hub before removal and reinstall
the rotor in the same position. Rotors with perceived hard spots or
discoloration should not be serviced. These conditions are normal. Installation
of new rotors does not require pad replacement. Do not replace pads unless their
condition requires it. It is not necessary to replace rotors in pairs. Rotors
may be replaced individually. However, caution should be exercised, as a
variance in surface finish may cause a brake pull condition.
A torque limiting socket or torque wrench must be used to insure that the wheel
nuts are tightened to specification. This should be done In 3 steps using the
star pattern:
1. Hand tighten all 5 lug nuts using the star pattern.
2. Tighten all 5 nuts to approximately 1/2 spec. using the star pattern.
3. Tighten all 5 nuts to full spec. using the star pattern.
Never use lubricants or penetrating fluids on wheel studs, nuts or mounting
surfaces. Wheel nuts, studs, and mounting surfaces must be clean and dry.
Brake Service Techniques
1. Clean and lubricate all rnetal-to-metal contact points (i.e. caliper to
knuckle, pad to knuckle, etc).
2. Clean and lubricate slide pins, if applicable.
3. Set correct clearances (i.e. caliper to knuckle, etc), if applicable.
4. Clean rotor and hub mounting surfaces. Use Kent Moore tool J-42450 to clean
around the wheel studs.
5. Verify lateral runout of the rotor with a dial indicator (rotor held on hub
with 3 or more wheel nuts and washers).
Important: Refer to the appropriate Service Manual for more specific procedures-
Pulsation
Important: Brake pulsation is often caused by factors outside customer control.
In these instances, the repair is covered under the GM New Vehicle Warranty.
Brake pulsation concerns may result from two basic conditions:
Pulsation is caused by brake rotor thickness variation. Thickness variation
causes the piston in the brake caliper to "pump" in and out of the caliper
housing. This "pumping" effect is transmitted hydraulically to the brake pedal.
Thickness variation on a new rotor will be virtually undetectable. But if the
rotor (as installed on the vehicle) has lateral runout, it is likely that
thickness variation will develop. Pulsation caused by thickness variation will
develop on new vehicles when the tolerances of the hub and rotor stack up with
lateral runout in excess of 0.080mm (0.003 in). Pulsation that is the result of
excessive lateral runout usually develops in 4800 -11300 kilometers (3000 -7000
miles). Thickness variation can be induced when uneven torque is applied to
wheel nuts (lug nuts). Improper wheel tightening after tire rotation, spare tire
usage. brake inspection, etc. can be the cause of pulsation- Again, it usually
takes 4800 -11300 kilometers (3000-7000 miles) after this event for the
condition to surface. The owner or driver does not usually make the connection
between the service event and the awareness of the pulsation.
The proper usage of torque wrenches and/or torque sticks (torque limiting
sockets) will greatly reduce or eliminate the pulsation conditions after wheel
service events.
The improper use of impact wrenches on wheel nuts greatly increases the
likelihood of pulsation after wheel service.
GM highly recommends the use of on-car brake rotor turning as a method of
eliminating the stack up of lateral runout which is a potential source of brake
pulsation. GM has identified superior equipment through testing and evaluation.
The *Pro-Cut PFM900 will consistently deliver machined rotors that meet GM
specifications (lateral runout less than 0.080 mm (0.003 in) and is the only
on-car brake lathe that is currently recommended by GM. The use of this on-car
rotor turning technology has proven to significantly reduce the repeat
occurrences of brake pulsation.
*We believe this source and their equipment to be reliable. There may be
additional manufacturers of such equipment. General Motors does not endorse,
indicate any preference for or assume any responsibility for the equipment from
this firm or for any such items which may be available from other sources.
The following are examples of pulsation conditions and reimbursement
recommendations:
1. If a customer noticed the condition after 4800-11300 kilometers (3000-7000
miles) and it gradually got worse, normally the repair would be covered. The
customer may tolerate the condition until it becomes very apparent.
2. If a customer indicated they had wheel service, ask who performed the
service. Then:
- If a dealer performed the service, consider paying for the repair and then
strongly reinforce the use of torque sticks at that dealer. Two common size
torque sticks cover 90% of all GM products. Each technician needs to use torque
sticks properly every time the wheel nuts are tightened.
- If the customer had the wheel service done outside of our dealer network.
normally GM would not offer any assistance.
Customer assistance concerning brake pulsation and brake wear should always take
into account the individual circumstances on a case by case basis. The
recommendations mentioned previously should only be used as a general guide.
REMEMBER THAT CUSTOMER SATISFACTION IS CRITICAL TO GM AND THAT OFTEN IT IS IN
GM'S BEST INTEREST TO SATISFY AND EDUCATE THE CUSTOMER CONCERNING FUTURE BRAKE
SERVICE.
Rotor Grooving
Excessive grooving can be caused by foreign material in contact with the rotor,
but most often rotor grooving is the result of normal brake wear. Do not
resurface rotors for light grooving. Resurface rotors only when grooves of 1.5
mm (0.060 in) or deeper are present.
A dime may be used to determine disc brake groove depth. Place a dime in the
groove, with Roosevelt's head toward the groove. If the dime goes into the
groove beyond the top of his head, the groove exceeds 1.5 mm (0.060 in) and the
rotor should be serviced. In Canada, if any portion of the letters of "Canada"
are covered, the rotor should be serviced. If the groove is too narrow for the
dime to be inserted, it is not a cause for concern.
High Pedal Effort
Follow the Service Manual diagnostic procedures for this condition. Service
(replace or resurface) rotors if they have been recently resurfaced. The surface
finish may be out-of-specification.
Lightly Rusted Rotors
Light surface rust on rotor braking surfaces is often cosmetic and ran be
eliminated during a few normal driving stops. Rusting may occur when a vehicle
is not driven for extended periods. Rotors with surface rust on unsold new cars
can usually be burnished clean by performing 15 moderate stops from 62-75 km/h
(35-40 mph) with cooling time between stops.
Facts About Brake Noise
Brake noise is normal and differences in loading, type of driving, or driving
style can make a difference in brake wear on the same make and model. Depending
on weather conditions, driving patterns and the local environment, brake noise
may become more or less apparent.
Brake noise is caused by a "slip stick" vibration of brake components. While
intermittent brake noise may be normal, performing 3-4 aggressive stops may
temporarily reduce or eliminate most brake squeal. If the noise persists, a
brake dampening compound may be applied to the back of each pad. Use Permatex
Disc Brake Quiet #126hb, or equivalent. Also, clean and lubricate all
metal-to-metal contact areas between pads, pad guides, caliper and knuckles with
a thin layer of high temperature silicon grease. This allows parts to slide
freely and not vibrate when moving relative to each other.
The following noises are characteristic of all braking systems and are
unavoidable. They may not indicate improper operation of the brake system.
Squeak/Squeal Noise
Occurs with front semi-metallic brake pads at medium speeds when light to medium
pressure is applied to the brake pedal.
Occasionally a noise may occur on rear brakes during the first few stops or with
cold brakes and/or high humidity.
Grinding Noise
Common to rear brakes and some front disc brakes during initial stops after the
vehicle has been parked overnight.
Caused by trace corrosion on the metal surfaces during vehicle non-use. Usually
disappears after a few stops.
Groan Noise
A small groan may be heard when stopping quickly or moving forward slowly from a
complete stop. This is normal.
Brake Wear
Several factors impact brake lining wear and should be taken into account when
reviewing related issues. The following are conditions that may accelerate brake
lining wear.
- Heavy loads
- High temperatures
- Towing
- Mountainous terrain
- City Driving
- Aggressive driving
- Driver braking characteristics (left foot)
The following are conditions that rnay extend brake lining wear:
- Light loads
- Highway driving
- Conservative driving
- Level terrain

BBA wrote:

> LMAO >>> Maybe you should consider actually reading the page before
> posting i.e: this is a GM Service Bulletin!!!!! I take it you don't
> actually know what it is that you are talking about!!! not a question
> >> is a matter of fact!!!
>
> Here's what it really says:

> and parallelism between mounting and friction surfaces. New rotors
> SHOULD NOT be resurfaced before installation.

Why are you quoting this bulletin when it conflicts with what you
have said in previous posts? I would agree with the bulletin....there
is no need to resurface a new rotor. If you have to resurface a "new"
rotor....it was junk to begin with. I don't know what kind of brake
shop would be turning new rotors....basically, they would be ripping
the customer off....giving them rotors that are no longer "new".

The real reason why GM has released this on-car brake rotor lathe
(we have one now at our dealership) is because of the captured
rotors on the Colorado line of trucks. It is pretty slick, I've used
it with great success on the captured rotors that are on the 3/4
ton trucks. Saves lots of time and you get a great cut.

Ian

On Wed, 12 Jan 2005 20:36:58 -0800, "BBA"
> wrote:

>LMAO >>> Maybe you should consider actually reading the page before posting i.e:
>this is a GM Service Bulletin!!!!! I take it you don't actually know what it is
>that you are talking about!!! not a question >> is a matter of fact!!!
>
>Here's what it really says:

You really -are- retarded, yah?
I mean _really_ retarded, and you have my condolences.
That notwithstanding, cutting out the horse**** and quoting from what
you now claim is YOUR source of information, it still says:

snip*
>New rotors SHOULD NOT be
>resurfaced before installation.

Now where do you want to hide?

I gave the ****ing URL ! Are you so goddamn stupid that you think I
didn't read it? So ****ing retarded you think I didn't know it was a
GM Service Bulletin ?

Jezus Christ on a ****in Crutch, SOMEBODY put that boy out of his
misery.

Lg

> >Here's what it really says:
>
> You really -are- retarded, yah?
> I mean _really_ retarded, and you have my condolences.
> That notwithstanding, cutting out the horse**** and quoting from what
> you now claim is YOUR source of information, it still says:
>
> snip*
> >New rotors SHOULD NOT be
> >resurfaced before installation.
>
> Now where do you want to hide?
>
> I gave the ****ing URL ! Are you so goddamn stupid that you think I
> didn't read it? So ****ing retarded you think I didn't know it was a
> GM Service Bulletin ?



You are truly a total and complete mindless idiot.!!

> Jezus Christ on a ****in Crutch, SOMEBODY put that boy out of his
> misery.




LOL >> Ever wonder why your life is so ****ed up? Most people are born with a
little common sense! Except in your case where as you are at an all time low! >>
Probably born in the negative margin - or possibly your lacking brain cells -
maybe when someone figures out what to do with stem-cell technology -- someone
may find a need to do some much needed maintenance on your cerebral cortex!

On Thu, 13 Jan 2005 04:14:23 GMT, the fly > wrote:

>>>> >Did you happen to have the rotors cut or resurfaced? i.e. happens to be a
>>>> >requirement when replacing a rotor!
>>>>
>>>> Foo!
>>>
>>>same to you pal!
>>>
>>>> Where did you get that nonsense!
>>>
>>>I don't know what where you come from! Here in the US most NITB rotors will
>>>require a base cut before installation
>>
>>To the dertiment of the customer's wallet and the benefit of the
>>mechanic's bottom line!
>
> Brake rotors (and drums) all tend to warp as the casting ages.
>They also get a lot of abuse in handling. The machining of hubs and
>mounting surfaces may be true to the friction surfaces when they're
>made at the factory, but after shipping, stocking, and even just
>months on the shelf, it's a different story. Some are worse than
>others, but they ALL need to be surfaced before installation. Anyone
>with experience on a brake lathe is aware of this, as is anyone with
>formal training in automotive technology.

Blather. http://www.babcox.com/editorial/bf/bf100326.htm

On Thu, 13 Jan 2005 04:56:04 -0800, John Ings >
wrote:

>Blather. http://www.babcox.com/editorial/bf/bf100326.htm

Wow, that is the most comprehensive treatsie on disc brake machining
I've ever seen.

One note, when I was a mechanic, the Chrysler engineering reps who
occasionally stopped by the shop told me that it was nearly impossible
to set up a disc such that it could be machined true to the hub when
it was reassembled on the vehical if it did not have either bearing
races, or a true machined surface.

This pretty much eliminated many frontwheel drive vehicals with disc
brake rotors that are simply slapped on and held in place when the
wheel is bolted on for disc brake machining.

You could have had hubs to bolt the rotors to, which could have been
then mounted on the brake lathe, but we never did that.

It would have been possible to machine them in place with the proper
equipment, but when we looked at that equipment it was so expensive
that management didn't even think twice. They didn't buy it.

I also wondered about machining rather than putting on new rotors.
Doing the job properly took a certain amount of time and when you
added that up versus simply cleaning up the hub and slapping on new
rotors, it did not seem like there was much difference, plus, the
customer was getting a brand new rotor.

By the way, I worked in Vermont, which is of course a stronghold of
salt use.

Corky Scott