Home » Public Forums » GMCnet » [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
| [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60493] |
Sat, 17 October 2009 23:16  |
fbhtxak
Messages: 191
Registered: April 2006
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For Ken Henderson and others who responded to my inquiry -
I went to Gene Fisher's site before posting but missed Dave Mumert's
excellent analysis. My objective is to reduce brake fade. He listed that as
an advantage for the wider shoes.
I descend steep mountain grades "out west" in such a way as to minimize
brake fade under ordinary circumstances. I, however, have long been
concerned about the risk of fade under emergency circumstances before I
could get the vehicle safely stopped. With very light traffic while
descending Raton Pass south on I 25 a few days ago, I tested the brakes for
fade under 'panic stop" conditions from about 55 mph. Deceleration was
acceptable until about 35 mph but the rate of deceleration slowed
considerably after that due to rear brake fade (I purposely avoided lockup
upon initial brake application). It then occurred to me that the larger
surface area of the wider shoes would at least delay brake fade on steep
mountain grades under "panic stop" conditions - and maybe enough to safely
stop the vehicle.
Other than the mountain grade situation described, I find the OEM brakes
otherwise adequate for the way I operate the vehicle.
Fred Hudspeth
'78 Royale - Tyler, TX
'82 Airstream Excella 28'Motorhome, Anchorage, AK
Date: Sat, 17 Oct 2009 19:38:06 -0400
From: Ken Henderson <ken0henderson@gmail.com>
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
To: gmclist@temp.gmcnet.org
Message-ID: <4ADA555E.6020900@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Fred,
I think John Evans has wider brake shoes available, but I don't think
they're as wide a 3".
Before committing to such a mod, one should read Dave Mumert's notes at
http://www.gmcmotorhomeinfo.com/brakes.html#calc
Ken H.
Fred Hudspeth wrote:
>
>
> Does anyone have a source for a kit to convert OEM rear brakes to 3" wide
> shoes? ...
> Fred Hudspeth
>
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60503 is a reply to message #60493] |
Sun, 18 October 2009 00:53  |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Fred,
If what your getting is truly a fade, You need to update to our rear
shoes.These are the same material California Highway Patrol runs on
the rear.
On Sat, Oct 17, 2009 at 9:16 PM, Fred Hudspeth <fbhtxak@sbcglobal.net> wrote:
> For Ken Henderson and others who responded to my inquiry -
>
> I went to Gene Fisher's site before posting but missed Dave Mumert's
> excellent analysis. My objective is to reduce brake fade. He listed that as
> an advantage for the wider shoes.
>
> I descend steep mountain grades "out west" in such a way as to minimize
> brake fade under ordinary circumstances. I, however, have long been
> concerned about the risk of fade under emergency circumstances before I
> could get the vehicle safely stopped. With very light traffic while
> descending Raton Pass south on I 25 a few days ago, I tested the brakes for
> fade under 'panic stop" conditions from about 55 mph. Deceleration was
> acceptable until about 35 mph but the rate of deceleration slowed
> considerably after that due to rear brake fade (I purposely avoided lockup
> upon initial brake application). It then occurred to me that the larger
> surface area of the wider shoes would at least delay brake fade on steep
> mountain grades under "panic stop" conditions - and maybe enough to safely
> stop the vehicle.
>
> Other than the mountain grade situation described, I find the OEM brakes
> otherwise adequate for the way I operate the vehicle.
>
> Fred Hudspeth
> '78 Royale - Tyler, TX
> '82 Airstream Excella 28'Motorhome, Anchorage, AK
>
>
>
> Date: Sat, 17 Oct 2009 19:38:06 -0400
> From: Ken Henderson <ken0henderson@gmail.com>
> Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
> To: gmclist@temp.gmcnet.org
> Message-ID: <4ADA555E.6020900@gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Fred,
>
> I think John Evans has wider brake shoes available, but I don't think
> they're as wide a 3".
>
> Before committing to such a mod, one should read Dave Mumert's notes at
>
> http://www.gmcmotorhomeinfo.com/brakes.html#calc
>
> Ken H.
>
> Fred Hudspeth wrote:
>>
>>
>> Does anyone have a source for a kit to convert OEM rear brakes to 3" wide
>> shoes? ...
>> Fred Hudspeth
>>
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
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--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
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jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60511 is a reply to message #60494] |
Sun, 18 October 2009 07:26 |
Gary Casey
Messages: 448
Registered: September 2009
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I was working on brake designs at GM during the drum-to-disk conversion (yup, a long time ago) and here were some of the comparisons as I understood them at the time:
1. Drums are cheaper. And at the time some cars were sold without boosters. Disk brakes required boosters, further increasing the cost.
2. Drum brakes were lighter (yes, people worried about weight back then. Just not very much). In a drum the structure also absorbs the heat, doing double duty (the apply force tends to expand the drum, which is also the heat sink). In a disk the heat sink (disk) sees essentially none of the apply force as it is all absorbed by the caliper, a structurally inefficient device (i.e. heavy) that absorbs none of the heat.
3. Disk were inherently more resistant to fade. The heat from the drum has to be conducted through the drum to the outside, so the friction surface could be at a much higher temperature than the outside. The drum friction surface has no access to cooling air. The disks conduct heat to the air directly from the friction surface, much more effective, and most of the friction surface is not covered by the friction material (it's out in the open). The "ventilation" slots in the more massive rotors were there primarily for structural stability, not cooling. Disk brakes were first to appear in Europe where the driving styles tended toward repetitive aggressive use of the brakes. The big three OEM thought brakes were for when you needed to pull into a rest stop after cruising for two hours, and that's all. See comment from Gene below - perfect disk brake scenario.
4. Drum brake friction material tends to have a higher variation in coefficient, and especially has a time dependance. On a sudden application from cold the coefficient can be very high, locking the brakes on a sudden panic stop. This was blamed for numerous accidents. This effect takes only a split second to go away, but sometimes the wheel is locked before that can happen. Experienced testers knew to warm the brakes just a bit before doing the panic stop test.
5. Disk brake friction material, because of all the compromises that went into it, tended to have a more consistent coefficient at different speeds, where the drum material had a "speed fade" characteristic.
6. As the drum got hot, it expanded away from the shoes, so the pedal would drop as the drum heated. Unless the shoes were well adjusted you could run out of pedal before fade, not good. In a disk none of the thermal expansion lowers the pedal.
7. Parking was a break even. If a drum parking brake was applied when the drum was hot it might lock on (couldn't release the latch) when the drum cooled and you couldn't move the car - and the drum could warp from the high stress. A disk brake cools away from the caliper, tending to release the parking brake upon cooling. The disk wins by a nose. A disk brake parking mechanism is more expensive than that in a drum brake(see point number 1).
8. The disk required much lower initial pressure for gentle stops. The first disk brakes had the pistons spring-loaded against the rotor so they were always rubbing. What can I say, gas was cheap. Now disk brake pistons retract, but the initial apply pressure is still very low. Drums, if one brake was adjusted slightly different than another had a tendency to pull one way or the other as one would start to apply before the other.
9. It was easier to design "center point steering" with disks as the lower ball joint could be further outboard.
10. Self adjusters on drum brakes are troublesome (understatement!), where disk brake adjusters are not (usually). But disk brakes use fluid during wear and drums do not, so the disk brake master cylinder reservoir has to be larger.
I was busy working on a multi-disk oil-cooled brake, but that's another story. The above comments are not mine an I have no axe to grind one way or the other. Just thought it might be interesting to read some of the comments from the experts I knew. The first year Toro had drum brakes in front and couldn't make one stop from 100 mph. The disk-brake Toro could make two(one max-G stop, WOT to 100 followed by another max-G stop). Our wet brake could make that stop an infinite number of times.
Gary, sorry about using up the bandwidth, Casey
________________________________
From: Mr.erf ERFisher <mr.erfisher@gmail.com>
To: gmclist@temp.gmcnet.org
Sent: Sat, October 17, 2009 10:31:20 PM
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
I would have to do some reading, but I think it was Frank Condo's analysis
that showed the heating and expansion of the drums was almost as large a
cause of ,drum brake, fade, as the brake material (esp. carbon Metallic
brake shoes)
this was why I went to disk brakes, I could not hold my brakes going down
the Grapevine (CA) towing a Tracker without brakes. Now I can run at any
speed with out fade.
gene
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60514 is a reply to message #60511] |
Sun, 18 October 2009 08:19 |
 |
USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Gary,
I, for one, appreciate the insight guys like yourself and others involved
with the auto industry bring to this forum.
Thanks,
Rob Mueller
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
'75 Avion - USA - The Parts Coach TZE 365V100324
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Gary Casey
Sent: Sunday, October 18, 2009 11:27 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
Gary, sorry about using up the bandwidth, Casey
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60524 is a reply to message #60494] |
Sun, 18 October 2009 09:30 |
Terry Skinner
Messages: 379
Registered: January 2004
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I gotta agree with Gene. To truly get away from fade disc brakes will
do you more good along with the correct material in the pads.
Reference Arch's search for the perfect brakes. He did the most good
with the material in the pads..........Terry
On Sat, Oct 17, 2009 at 9:31 PM, Mr.erf ERFisher <mr.erfisher@gmail.com> wrote:
> I would have to do some reading, but I think it was Frank Condo's analysis
> that showed the heating and expansion of the drums was almost as large a
> cause of ,drum brake, fade, as the brake material (esp. carbon Metallic
> brake shoes)
>
> this was why I went to disk brakes, I could not hold my brakes going down
> the Grapevine (CA) towing a Tracker without brakes. Now I can run at any
> speed with out fade.
>
> gene
>
>
>> I went to Gene Fisher's site before posting but missed Dave Mumert's
>> excellent analysis. My objective is to reduce brake fade. He listed that as
>> an advantage for the wider shoes.
>>
>> --
> Gene Fisher -- 74-23,77PB/ore/ca
> “Give a man a fish; you have fed him for today --- give him a URL and
> -------
> http://gmcmotorhome.info/
> Alternator Protection Cable
> http://gmcmotorhome.info/APC.html
> _______________________________________________
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--
Terry Skinner
Roy. Washington
'76 GMC
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60525 is a reply to message #60493] |
Sun, 18 October 2009 09:35 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Very good. All characteristics we had experienced with both systems, but the "why" behind it all makes perfect sense now. OK ----you can't leave me hanging as I try to imagine the plumbing to get the cooling oil to and from the rotating member. You might not be able to divulge the design, but any clues? Has anyone put it into the mainstream?
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: [GMCnet] Oil-cooled brakes [message #60528 is a reply to message #60525] |
Sun, 18 October 2009 10:44 |
Gary Casey
Messages: 448
Registered: September 2009
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I've had a lot of fun projects over the years, but this was one of the most interesting. It didn't go anywhere, but I understand that Holden put a couple on some race cars - their version of the TransAm series. Off-road vehicles use them, but that's only distantly related. It all started in the transmission development group where I worked fresh out of school. Take some slight modified transmission clutch material (cardboard base) and cut a bunch of grooves in it just like a waffle iron, leaving square blocks of friction material. Steel plates go in between and I think we generally used about 3 friction plates with material on both sides for 6 friction surfaces. An annular piston pushed them together and there was a return spring to push them apart with a clever self-adjusting gismo made from roll pins. The steels were stationary and the clutch plates rotated.
The oil was pumped from the inside out, using the grooves as centrifugal pumps to help the flow. There was a centrifugal pump gear driven off the wheel in some applications. In the Toro the pump was centrifugal engine driven. On the Toro we only used them on the fronts, since the rear brakes were pretty much useless in a hard stop(and we hadn't designed a good parking brake). The heat was rejected by a heat exchanger in the slightly enlarged engine radiator. It was kind of synergistic - you only use the brakes when you're not using the engine, and vise versa. The oil was the trick and it was specially developed by Shell. Very low in viscosity and it had friction modifiers similar to transmission oil. Almost like kerosene.
There were a lot of advantages. A lot of brake could be put inside a small wheel. There was no fade, period. The coefficient stayed constant until the fluid boiled and then the friction material just disintegrated and the brake welded itself together. We did some tests going down mountains with no fluid. Stopped just fine, but had to have wrecker to move the car afterward. There was virtually no wear, so in the pass car version the halves of the housing were welded together - looked sort of like a torque converter (we were in the transmission group:-). I thought the feel was fantastic. The static coefficient was low, so you could pull to a stop without the undignified jerk you get with dry materials, which all have a high static. You could nail the brake and any speed and get exactly the same response every time.
The first project was before my time and it was a truck brake used on trailers - self-contained with a radiator on the front. The final test was to go east from Loveland pass (before the tunnel existed), fully loaded in neutral and then pull into the restaurant at Georgetown. Passed a lot of trucks on the way, and I'm told some of the other drivers pulled into Georgetown thinking they'd see a ghost. I'm sure there was no truck, drum or disk, that had even half the heat rejection capacity.
Why did it go away? I could blame politics - we were the transmission group competing against the brake group, who got to make the final decision. But actually, friction was the culprit. We couldn't get the brake-off drag to zero and by using retractors the next-gen disks had zero drag. Our drag was about the same as the first-gen disk brakes. The other was cost - it just couldn't compete with a dry system that needed no pump.
Gary, lots of miles in a wet-brake Toro, Casey
They were awesome brakes, though.
________________________________
From: John R. Lebetski <gransport@aol.com>
To: gmclist@temp.gmcnet.org
Sent: Sun, October 18, 2009 8:35:32 AM
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
Very good. All characteristics we had experienced with both systems, but the "why" behind it all makes perfect sense now. OK ----you can't leave me hanging as I try to imagine the plumbing to get the cooling oil to and from the rotating member. You might not be able to divulge the design, but any clues? Has anyone put it into the mainstream?
--
John Lebetski
Chicago, IL
77 Eleganza II
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60529 is a reply to message #60511] |
Sun, 18 October 2009 10:45 |
Tin Gerbil
Messages: 236
Registered: October 2006
Location: Vancouver Island, B.C.
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Gary;
Why/how can a disk turn red hot if it "sees essentially none of the
apply force"? Why do disks crack and warp?
Thanks;
Gordon
Gary Casey wrote:
> I was working on brake designs at GM during the drum-to-disk
> conversion (yup, a long time ago) and here were some of the
> comparisons as I understood them at the time:
In a disk the heat sink (disk) sees essentially none of the apply
force as it is all absorbed by the caliper, a structurally inefficient
device (i.e. heavy) that absorbs none of the heat.
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Gordon
'74 Canyon Lands "Tin Gerbil"
Vancouver Island, B.C.
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60534 is a reply to message #60529] |
Sun, 18 October 2009 11:30 |
Gary Casey
Messages: 448
Registered: September 2009
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Good question and I didn't explain myself very well. The rotor is only squeezed by the apply force so the stress level from that is very low. Then the actual torque is restrained mostly by the hub portion and that part doesn't directly see the heat. The point is that given the size of the rotor, the mechanical loads are very low. Warpage, cracking ,etc. is usually due to thermal stress, not the mechanical loading from the caliper and pads. One problem with disks is that they might not be exactly a constant thickness. When this happens the high spot takes more of the load and gets hotter. It expands and gets even higher, leading to a rough brake. Often times that spot is then worn down just a little and the high spot will migrate somewhere else. It is a big problem in Germany and I think it's called "high-speed judder". Keeping the rotor straight and flat with all the thermal gradients is a real problem. Not that they can't crack from some
other reason, but the dominant cause of problems is thermal stress. Make sense?
Gary
________________________________
From: Gordon <wizwing@telus.net>
To: gmclist@temp.gmcnet.org
Sent: Sun, October 18, 2009 9:45:38 AM
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
Gary;
Why/how can a disk turn red hot if it "sees essentially none of the
apply force"? Why do disks crack and warp?
Thanks;
Gordon
Gary Casey wrote:
> I was working on brake designs at GM during the drum-to-disk
> conversion (yup, a long time ago) and here were some of the
> comparisons as I understood them at the time:
In a disk the heat sink (disk) sees essentially none of the apply
force as it is all absorbed by the caliper, a structurally inefficient
device (i.e. heavy) that absorbs none of the heat.
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60536 is a reply to message #60534] |
Sun, 18 October 2009 11:55 |
Tin Gerbil
Messages: 236
Registered: October 2006
Location: Vancouver Island, B.C.
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Gary;
We have 5 GM's in the family and have given up changing rotors in an
attempt to eliminate the "judder". From cheap offshore to genuine GM,
50% of them warp. I never understood why before, I just assumed it was
from getting a blast of water on a hot rotor, not inconsistent rotor
thickness. When you see fellows in the orient jumping on wooden plugs,
in the riverbank mud, where they pour their cast iron, you wonder why
our brakes continue to work at all? This may be where our master
cylinders, wheel cylinders and other castings come from.
Thanks;
Gordon
Gary Casey wrote:
> Good question and I didn't explain myself very well. The rotor is
> only squeezed by the apply force so the stress level from that is
> very low. Then the actual torque is restrained mostly by the hub
> portion and that part doesn't directly see the heat. The point is
> that given the size of the rotor, the mechanical loads are very low.
> Warpage, cracking ,etc. is usually due to thermal stress, not the
> mechanical loading from the caliper and pads. One problem with disks
> is that they might not be exactly a constant thickness. When this
> happens the high spot takes more of the load and gets hotter. It
> expands and gets even higher, leading to a rough brake. Often times
> that spot is then worn down just a little and the high spot will
> migrate somewhere else. It is a big problem in Germany and I think
> it's called "high-speed judder". Keeping the rotor straight and flat
> with all the thermal gradients is a real problem. Not that they
> can't crack from some other reason, but the dominant cause of
> problems is thermal stress. Make sense? Gary
>
>
>
> ________________________________ From: Gordon <wizwing@telus.net> To:
> gmclist@temp.gmcnet.org Sent: Sun, October 18, 2009 9:45:38 AM
> Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
>
> Gary; Why/how can a disk turn red hot if it "sees essentially none of
> the apply force"? Why do disks crack and warp? Thanks; Gordon
>
> Gary Casey wrote:
>> I was working on brake designs at GM during the drum-to-disk
>> conversion (yup, a long time ago) and here were some of the
>> comparisons as I understood them at the time:
> In a disk the heat sink (disk) sees essentially none of the apply
> force as it is all absorbed by the caliper, a structurally
> inefficient device (i.e. heavy) that absorbs none of the heat.
>
> _______________________________________________ GMCnet mailing list
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>
>
>
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Gordon
'74 Canyon Lands "Tin Gerbil"
Vancouver Island, B.C.
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60538 is a reply to message #60536] |
Sun, 18 October 2009 13:43 |
Gary Casey
Messages: 448
Registered: September 2009
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An interesting historical observation - don't know if it is still true or not, but judging from Gordon's comment it might be. Once upon a time, all GM cars had notorious problems with their rotors - they were constantly going out of true and causing a pulsating pedal (similar, but not quite the same as the high speed judder I wrote about). The very same brake design was used by Cadillac - this was back in the "good ol' days when each division actually controlled what they built. Why didn't Cadillac have the same problems? Everyone bought their rotors from Central Foundry, the cheapest supplier. That is, all except Cadillac, who bought them from Kelsey Hayes. Same design, different and probably more expensive iron chemistry and foundry process. Every time the rotor gets really hot it actually goes through a heat treat process and changes grain structure. If the carbon content isn't really uniform throughout there will inconsistent dimensional
changes. Grind the rotors and they might stay for a while - or might not. A losing proposition.
Where do they come from now? Gordon probably nailed it - or they come from a domestic supplier trying desperately to cheapen is product enough to compete with the Chinese.
________________________________
Gary;
We have 5 GM's in the family and have given up changing rotors in an
attempt to eliminate the "judder". From cheap offshore to genuine GM,
50% of them warp. I never understood why before, I just assumed it was
from getting a blast of water on a hot rotor, not inconsistent rotor
thickness. When you see fellows in the orient jumping on wooden plugs,
in the riverbank mud, where they pour their cast iron, you wonder why
our brakes continue to work at all? This may be where our master
cylinders, wheel cylinders and other castings come from.
Thanks;
Gordon
G
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60539 is a reply to message #60538] |
Sun, 18 October 2009 14:21 |
Tin Gerbil
Messages: 236
Registered: October 2006
Location: Vancouver Island, B.C.
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Gary;
Very interesting. The current worst one of the lot is my son's '98
Cadillac Concours. The rotors were found to be too thin by the local GM
dealer and according to the documentation that came with the vehicle,
changed using new GM rotors. We have repeatedly stopped suppliers from
trying to give sell new rotors when in fact they cleanup at over the
minimum thickness. Every time you ask for pads, the suppliers will tell
you the rotors are worn out. The last was on my '98 S-10. Our
experience is a used rotor will not warp as often or as badly as a new
one. Once the material has gone through years of heat cycles, it seems
to become more stable.
Gordon
Gary Casey wrote:
> An interesting historical observation - don't know if it is still
> true or not, but judging from Gordon's comment it might be. Once
> upon a time, all GM cars had notorious problems with their rotors -
> they were constantly going out of true and causing a pulsating pedal
> (similar, but not quite the same as the high speed judder I wrote
> about). The very same brake design was used by Cadillac - this was
> back in the "good ol' days when each division actually controlled
> what they built. Why didn't Cadillac have the same problems?
> Everyone bought their rotors from Central Foundry, the cheapest
> supplier. That is, all except Cadillac, who bought them from Kelsey
> Hayes. Same design, different and probably more expensive iron
> chemistry and foundry process. Every time the rotor gets really hot
> it actually goes through a heat treat process and changes grain
> structure. If the carbon content isn't really uniform throughout
> there will inconsistent dimensional changes. Grind the rotors and
> they might stay for a while - or might not. A losing proposition.
>
> Where do they come from now? Gordon probably nailed it - or they
> come from a domestic supplier trying desperately to cheapen is
> product enough to compete with the Chinese.
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Gordon
'74 Canyon Lands "Tin Gerbil"
Vancouver Island, B.C.
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60594 is a reply to message #60591] |
Sun, 18 October 2009 22:20 |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
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Senior Member |
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I don't know about the used rotor idea. On both my Saturn and my Caravan by the time the pads are worn out the rotors are beyond hope.
It works better to just buy new rotors with the pads.
And then Bed them in properly
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60597 is a reply to message #60514] |
Sun, 18 October 2009 22:35 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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Me too....Thanks
| Robert Mueller wrote on Sun, 18 October 2009 08:19 |
Gary,
I, for one, appreciate the insight guys like yourself and others involved
with the auto industry bring to this forum.
Thanks,
Rob Mueller
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
'75 Avion - USA - The Parts Coach TZE 365V100324
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Gary Casey
Sent: Sunday, October 18, 2009 11:27 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
Gary, sorry about using up the bandwidth, Casey
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Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes [message #60615 is a reply to message #60594] |
Mon, 19 October 2009 00:34 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Keith,
Here in Australia I have a Mazda Tribute. When I took it in for the 40,000km
(24,484mi) check I was told that the brake pads and disks were shot.
I looked at them and I couldn't believe how worn the disks were. I noted
that to the service writer who promptly told me that Mazda was using Formula
1 technology brake disks that were softer so that their cars would stop
better. I gave him a "what a bunch of BS look" and noted that I would take
care of it myself. One of the other service writers that knew me walked over
and told me just to go buy a new set of pads and carefully bed them in. When
the car got to 60,000km I bit the bullet and bought a new set of rotors
(aftermarket made in Australia) and the pads the rotor maker recommended for
good stopping and wear. The car stopped just as well as with the OEM rotors
and pads. I've been keeping an eye on them and the rotors are definitely not
wearing as fast as the OEM's.
Regards,
Rob Mueller
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
'75 Avion - USA - The Parts Coach TZE 365V100324
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Keith V
Sent: Monday, October 19, 2009 2:21 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] Converting OEM Rear Brakes to 3" Wide Shoes
I don't know about the used rotor idea. On both my Saturn and my Caravan by
the time the pads are worn out the rotors are beyond hope.
It works better to just buy new rotors with the pads.
And then Bed them in properly
--
Keith
69 Vette
29 Dodge
75 Royale GMC
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Regards,
Rob M. (USAussie)
The Pedantic Mechanic
Sydney, Australia
'75 Avion - AUS - The Blue Streak TZE365V100428
'75 Avion - USA - Double Trouble TZE365V100426
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