GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.

Home » Public Forums » GMCnet » Re: [GMCnet] Six wheel disks?
Re: [GMCnet] Six wheel disks? [message #328963] Thu, 08 February 2018 21:23 Go to next message
THOMAS R WHITTON is currently offline  THOMAS R WHITTON   United States
Messages: 47
Registered: September 2016
Karma: -1
Member

Did Lee Harrison ever furnish disks on all four rear wheels or disks on the middle wheels only with drums in the rear?
Tom Whitton26 foot updated GMCPaducah, KY
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328964 is a reply to message #328963] Thu, 08 February 2018 21:32 Go to previous messageGo to next message
powwerjon is currently offline  powwerjon   United States
Messages: 849
Registered: March 2013
Karma: -2
Senior Member
Leigh offered both the mid bogie and rear bogie disk brake kits. They are no longer available as far as I know. The best mid bogie brake setup is the Dave Lenzi unit out there right now, it is a massive brake system that also allows for an emergency caliper on the rotor. You only really need to have disks on the mid bogie and a drum set on the rear. Call call Dave and talk to him.

J.R. Wright
GMC GreatLakerTech Editor
78 Buskirk 30' Stretch
75 Avion Under Reconstruction
Michigan

> On Feb 8, 2018, at 8:23 PM, THOMAS R WHITTON wrote:
>
>
> Did Lee Harrison ever furnish disks on all four rear wheels or disks on the middle wheels only with drums in the rear?
> Tom Whitton26 foot updated GMCPaducah, KY
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328965 is a reply to message #328963] Thu, 08 February 2018 21:32 Go to previous messageGo to next message
Sammy Williams is currently offline  Sammy Williams   United States
Messages: 522
Registered: August 2010
Karma: -2
Senior Member
I seem to remember a set of center drums (to save money) and an all disc
set for performance. :)
Sammy

On Feb 8, 2018 21:23, "THOMAS R WHITTON" wrote:

>
> Did Lee Harrison ever furnish disks on all four rear wheels or disks on
> the middle wheels only with drums in the rear?
> Tom Whitton26 foot updated GMCPaducah, KY
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328973 is a reply to message #328963] Fri, 09 February 2018 07:41 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
We put six wheel disks and tru-traks on Stick Miller's second coach, replacing the big mid wheel disk that Lee Haeeison provrided. I don't think it made a great difference either way. Around here, rear drums with reaction arms do as well for less money. The rear disks >might< have an advantage in the mountains.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Six wheel disks? [message #328982 is a reply to message #328973] Fri, 09 February 2018 10:28 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
We used to say in drag racing, weight reduction by one pound is equal to 2
horsepower gained. If you really want your coach to stop as well as
possible, leave the anvil at home as well as the stump it is mounted on.
Keep weight as far to the rear of the coach as practical, and as low as
possible. If you don't pack it along, you don't have to burn gas to
accelerate it, nor wear out brake lining trying to stop it. But, you
already know that, right?
I have installed most of the improved braking systems out there, and
by far, hands down, the most effective system at stopping the coach is a 6
wheel all disc system with a 1 ton front end with 11 inch rotors, and
reaction arms on the four rear rotors. I prefer using the standard master
cylinder, BUT, YOU GOT TO CHECK THE FLUID OFTEN IF YOU USE IT instead of
the P-30. Convert your original distribution valve to all disc, or replace
it with an all disc valve.
The trade off with this all disc system is no parking brake. I have
never set my parking brake since the first time I drove the coach after I
bought it. The cables were rusty and sticky and did not release after I
applied them. I very soon had smoking rear brakes. After several attempts
to repair them, including new rear cables, and a pulley system on the
forward cable, I quit pulling on the parking brake.
Reaction arm brakes will make your coach stop like a modern
automobile, and make everything in your coach that is not nailed down
subject to movement.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Feb 9, 2018 5:44 AM, "Johnny Bridges via Gmclist" <
gmclist@list.gmcnet.org> wrote:

> We put six wheel disks and tru-traks on Stick Miller's second coach,
> replacing the big mid wheel disk that Lee Haeeison provrided. I don't
> think it
> made a great difference either way. Around here, rear drums with reaction
> arms do as well for less money. The rear disks >might< have an advantage
> in the mountains.
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328993 is a reply to message #328982] Fri, 09 February 2018 15:43 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Jim,

Some states require a mechanically actuated emergency brake. That's why I left the drums on the rears when I first registered it in
New Jersey.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of James Hupy
Sent: Saturday, February 10, 2018 3:29 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Six wheel disks?

We used to say in drag racing, weight reduction by one pound is equal to 2
horsepower gained. If you really want your coach to stop as well as
possible, leave the anvil at home as well as the stump it is mounted on.
Keep weight as far to the rear of the coach as practical, and as low as
possible. If you don't pack it along, you don't have to burn gas to
accelerate it, nor wear out brake lining trying to stop it. But, you
already know that, right?
I have installed most of the improved braking systems out there, and
by far, hands down, the most effective system at stopping the coach is a 6
wheel all disc system with a 1 ton front end with 11 inch rotors, and
reaction arms on the four rear rotors. I prefer using the standard master
cylinder, BUT, YOU GOT TO CHECK THE FLUID OFTEN IF YOU USE IT instead of
the P-30. Convert your original distribution valve to all disc, or replace
it with an all disc valve.
The trade off with this all disc system is no parking brake. I have
never set my parking brake since the first time I drove the coach after I
bought it. The cables were rusty and sticky and did not release after I
applied them. I very soon had smoking rear brakes. After several attempts
to repair them, including new rear cables, and a pulley system on the
forward cable, I quit pulling on the parking brake.
Reaction arm brakes will make your coach stop like a modern
automobile, and make everything in your coach that is not nailed down
subject to movement.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Feb 9, 2018 5:44 AM, "Johnny Bridges via Gmclist" <
gmclist@list.gmcnet.org> wrote:

> We put six wheel disks and tru-traks on Stick Miller's second coach,
> replacing the big mid wheel disk that Lee Haeeison provrided. I don't
> think it
> made a great difference either way. Around here, rear drums with reaction
> arms do as well for less money. The rear disks >might< have an advantage
> in the mountains.
>
> --johnny
> --
> 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> "I forgive them all, save those who hurt the dogs. They must answer to me
> in hell" - ol Andy, paraphrased
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Six wheel disks? [message #328994 is a reply to message #328993] Fri, 09 February 2018 17:12 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
USAussie wrote on Fri, 09 February 2018 16:43
Jim,

Some states require a mechanically actuated emergency brake. That's why I left the drums on the rears when I first registered it in
New Jersey.

Regards,
Rob M.
The Pedantic Mechanic

What any number of owners have not included in their thinking is that if the case that you take a hit to a drive axle, the final drive or the transmission after the direct clutch (where the parking pawl is), you could have no way to stop the vehicle from rolling if it chose to do so.

I did have my parking brake working, and it can be done.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: [GMCnet] Six wheel disks? [message #328995 is a reply to message #328994] Fri, 09 February 2018 18:02 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
I work on these coaches all the time. If an owner wants his parking brake
to work, then it gets Albert B's kit. Then they work marginally well, as a
parking brake. Emergency brake? Not so much. But you absolutely MUST
EXERCIZE the cables. Sitting a long time with the parking brake set will
almost guarantee dragging brakes. I have read the D.O.T. mandate on
emergency/parking brakes. They must be a whole separate system, applied by
hand or foot. A line lock hydraulic system is not approved. So, I don't
install them. Wheel chocks work quite well. Owners can do to their own
coaches whatever they choose and feel confident with. Me, I don't want the
liability.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Feb 9, 2018 3:13 PM, "Matt Colie" wrote:

> USAussie wrote on Fri, 09 February 2018 16:43
>> Jim,
>>
>> Some states require a mechanically actuated emergency brake. That's why
> I left the drums on the rears when I first registered it in
>> New Jersey.
>>
>> Regards,
>> Rob M.
>> The Pedantic Mechanic
>
> What any number of owners have not included in their thinking is that if
> the case that you take a hit to a drive axle, the final drive or the
> transmission after the direct clutch (where the parking pawl is), you
> could have no way to stop the vehicle from rolling if it chose to do so.
>
> I did have my parking brake working, and it can be done.
>
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328996 is a reply to message #328995] Fri, 09 February 2018 18:39 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Jim,

Dave Lenzi's new middle wheel disk system includes a hydraulic lock system that works.

A brake lever applies pressure to HEAVY spring which in turn presses on a hydraulic cylinder which applies pressure to a modified VW
front disk caliper.

As the brake system cools down the spring maintains pressure in cylinder and on the caliper.

Hopefully he'll bring it to Tucson so you can check it out.

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of James Hupy
Sent: Saturday, February 10, 2018 11:03 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Six wheel disks?

I work on these coaches all the time. If an owner wants his parking brake
to work, then it gets Albert B's kit. Then they work marginally well, as a
parking brake. Emergency brake? Not so much. But you absolutely MUST
EXERCIZE the cables. Sitting a long time with the parking brake set will
almost guarantee dragging brakes. I have read the D.O.T. mandate on
emergency/parking brakes. They must be a whole separate system, applied by
hand or foot. A line lock hydraulic system is not approved. So, I don't
install them. Wheel chocks work quite well. Owners can do to their own
coaches whatever they choose and feel confident with. Me, I don't want the
liability.
Jim Hupy
Salem, Or
78 GMC ROYALE 403



_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org



Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Six wheel disks? [message #328998 is a reply to message #328996] Fri, 09 February 2018 20:34 Go to previous messageGo to next message
Kosier is currently offline  Kosier   United States
Messages: 834
Registered: February 2008
Karma: 1
Senior Member
And if there is any kind of leak in the hydraulic system????

Gary Kosier
77PB w/500Cad
Newark, Ohio

--------------------------------------------------
From: "Rob Mueller"
Sent: Friday, February 09, 2018 7:39 PM
To:
Subject: Re: [GMCnet] Six wheel disks?

> Jim,
>
> Dave Lenzi's new middle wheel disk system includes a hydraulic lock system
> that works.
>
> A brake lever applies pressure to HEAVY spring which in turn presses on a
> hydraulic cylinder which applies pressure to a modified VW
> front disk caliper.
>
> As the brake system cools down the spring maintains pressure in cylinder
> and on the caliper.
>
> Hopefully he'll bring it to Tucson so you can check it out.
>
> Regards,
> Rob M.
> The Pedantic Mechanic
> Sydney, Australia
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
> USA '77 Kingsley - TZE 267V100808
>
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of James
> Hupy
> Sent: Saturday, February 10, 2018 11:03 AM
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] Six wheel disks?
>
> I work on these coaches all the time. If an owner wants his parking brake
> to work, then it gets Albert B's kit. Then they work marginally well, as a
> parking brake. Emergency brake? Not so much. But you absolutely MUST
> EXERCIZE the cables. Sitting a long time with the parking brake set will
> almost guarantee dragging brakes. I have read the D.O.T. mandate on
> emergency/parking brakes. They must be a whole separate system, applied by
> hand or foot. A line lock hydraulic system is not approved. So, I don't
> install them. Wheel chocks work quite well. Owners can do to their own
> coaches whatever they choose and feel confident with. Me, I don't want the
> liability.
> Jim Hupy
> Salem, Or
> 78 GMC ROYALE 403
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #328999 is a reply to message #328998] Fri, 09 February 2018 21:02 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
Messages: 4442
Registered: January 2004
Karma: 13
Senior Member
I was talking on the phone with Dave Lenzi today. He will have it at Tucson.

Emery Stora
77 Kingsley
Frederick, CO

> On Feb 9, 2018, at 7:34 PM, Gary Kosier wrote:
>
> And if there is any kind of leak in the hydraulic system????
>
> Gary Kosier
> 77PB w/500Cad
> Newark, Ohio
>
> --------------------------------------------------
> From: "Rob Mueller"
> Sent: Friday, February 09, 2018 7:39 PM
> To:
> Subject: Re: [GMCnet] Six wheel disks?
>
>> Jim,
>>
>> Dave Lenzi's new middle wheel disk system includes a hydraulic lock system that works.
>>
>> A brake lever applies pressure to HEAVY spring which in turn presses on a hydraulic cylinder which applies pressure to a modified VW
>> front disk caliper.
>>
>> As the brake system cools down the spring maintains pressure in cylinder and on the caliper.
>>
>> Hopefully he'll bring it to Tucson so you can check it out.
>>
>> Regards,
>> Rob M.
>> The Pedantic Mechanic
>> Sydney, Australia
>> AUS '75 Avion - The Blue Streak TZE365V100428
>> USA '75 Avion - Double Trouble TZE365V100426
>> USA '77 Kingsley - TZE 267V100808
>>
>>
>> -----Original Message-----
>> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of James Hupy
>> Sent: Saturday, February 10, 2018 11:03 AM
>> To: gmclist@list.gmcnet.org
>> Subject: Re: [GMCnet] Six wheel disks?
>>
>> I work on these coaches all the time. If an owner wants his parking brake
>> to work, then it gets Albert B's kit. Then they work marginally well, as a
>> parking brake. Emergency brake? Not so much. But you absolutely MUST
>> EXERCIZE the cables. Sitting a long time with the parking brake set will
>> almost guarantee dragging brakes. I have read the D.O.T. mandate on
>> emergency/parking brakes. They must be a whole separate system, applied by
>> hand or foot. A line lock hydraulic system is not approved. So, I don't
>> install them. Wheel chocks work quite well. Owners can do to their own
>> coaches whatever they choose and feel confident with. Me, I don't want the
>> liability.
>> Jim Hupy
>> Salem, Or
>> 78 GMC ROYALE 403
>>
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

Re: [GMCnet] Six wheel disks? [message #329002 is a reply to message #328999] Fri, 09 February 2018 21:43 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
I've always had serious qualms about any hydraulic-based parking brake
system because of the dramatic effect even a small fluid leak can have.
Dave's spring loaded system will probably overcome some of that problem.
But I think my system may be even better:

Several years ago, when the EBC Yellow brake pads first became available, I
wanted to do controlled tests on them. So, I fabricated a "brake pedal
puller" to mount beneath the GMC floorboard under the brake pedal. A chain
attaches the brake pedal to a pneumatic cylinder. Using a solenoid valve
system and a large air tank, to provide regulated pressure to that cylinder
on command, we were able to get some pretty well controlled test results --
the system even fired a paint ball on the pavement where the brake lights
came one.

A few years later, I realized one day that I'd never removed the "pedal
puller". Since I'd recently acquired a tiny Thomas air compressor, capable
of 100+ psi, it occurred to me that the two of them should work together
for some good purpose. What I wound up with is a 6-wheel (or 10-wheel if
towing) parking brake system. A dash switch activates the compressor to
produce 100 psi, pressure switch regulated. That 100 psi results in 140
lbf of brake pedal force. The compressor will maintain that pressure until
the engine battery runs dead -- a LONG time since, even with minor leakage,
the compressor runs for maybe 2 seconds out of every minute. Granted, a
hydraulic leak will also cause brake failure -- but only after it's leaked
the pedal all the way to the floor (in both the front and rear brake
systems). To release the brake, the dash switch is turned off, removing
power to the compressor, and to the normally-open solenoid valve which
dumps the trapped pressure.

It's really quite simple system and is very effective -- even without
vacuum boost, that 140 lbf on the brake pedal is darned effective with the
coach already stopped. It will even give a pretty dramatic stop with the
engine running. :-)

Just another idea to consider -- even if not a "legal" one for satisfaction
of DOT rules.

​Ken H.


> On Feb 9, 2018, at 7:34 PM, Gary Kosier wrote:
>>
>> And if there is any kind of leak in the hydraulic system????
>>
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Six wheel disks? [message #329015 is a reply to message #328963] Sat, 10 February 2018 08:04 Go to previous message
jhbridges is currently offline  jhbridges   United States
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
Senior Member
I have a pair of 20 inch 4x4 treated blocks which constitute the 'parking brake'. Never tried the handle, I was told it worked when I got the coach, but it has one of Ragusa's extensions to make it easier to set - and bend things if something sticks. Should I want or need the handbrake, I'll add pulleys per Tom Pryor in place of the slides.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Previous Topic: [GMCnet] Sienna seats
Next Topic: [GMCnet] GM net] Figured out how to count water pump impeller
Goto Forum:
  


Current Time: Thu Mar 28 04:35:27 CDT 2024

Total time taken to generate the page: 0.01289 seconds