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[GMCnet] Harrison Brakes [message #329379] Wed, 21 February 2018 16:09 Go to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
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Senior Member
I just got a call from a GMC old-timer wanting information about Leigh
Harrison brakes. Since I've never fooled with them, I couldn't help him
but offered to ask Y'All: Who's an "expert" I can connect him with?

Ken H.
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Harrison Brakes [message #329381 is a reply to message #329379] Wed, 21 February 2018 16:34 Go to previous messageGo to next message
cbryan   United States
Messages: 451
Registered: May 2012
Location: Ennis, Texas
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Senior Member
Ken,

I think Dave Lenzi knows a lot about them. He gave me helpful advice and had parts numbers for banjo fittings, etc. I was running for the longest time with only the mid brakes on my Harrison setup and was happy with their performance, as the fronts needed bleeding. When the mid brake line broke near the caliper from not having a hose attached, I had zero brakes. I ran into Montgomery, Texas, with only a slight vestige of brakes, and such a slight vestige, that it wouldn't hold the coach on the level at a stop unless the transmission was in neutral. Paul from Nova Scotia was my guru then and we got back home with good brakes. I don't know of another guru around. Like many running those Harrison setups, I like them. I know Jim Bounds does not like them. Stock for Jim or nothing. Can't blame him because of liability concerns, but I think the warranty is expired on the originals and if they fail, there's a green light for 'improvements'.

Carey


Carey from Ennis, Texas 78 Royale, 500 Cadillac, Rance Baxter EFI.

[Updated on: Thu, 22 February 2018 17:43]

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Re: [GMCnet] Harrison Brakes [message #329382 is a reply to message #329381] Wed, 21 February 2018 17:12 Go to previous messageGo to next message
94nubble is currently offline  94nubble   United States
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Location: Chesapeake VA
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What does he need Ken? Have him call me. I am on the Black List.


Tom McManus
1977 Royale
Chesapeake VA
Re: [GMCnet] Harrison Brakes [message #329384 is a reply to message #329382] Wed, 21 February 2018 17:46 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
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Carey & Tom,

Thanks, I've forwarded your info to him.

Ken H.


On Wed, Feb 21, 2018 at 6:12 PM, Tom McManus wrote:

> What does he need Ken? Have him call me. I am on the Black List.
>
> --
> Tom McManus
> 1977 Royale
>
> Chesapeake VA
>
> _______________________________________________
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Harrison Brakes [message #329396 is a reply to message #329384] Thu, 22 February 2018 06:56 Go to previous messageGo to next message
Kimberlea Weeks is currently offline  Kimberlea Weeks   United States
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Registered: July 2010
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Albert Branscombe was able to help us with our Harrison brakes.

Kimberlea Weeks | GMC Motorhomes International
1402 So. Cage Blvd., Unit 273 | Pharr, TX 78577-6288
612.501.4600 | f.866.519.0047 | www.gmcmi.com

On Wed, Feb 21, 2018 at 5:46 PM, Ken Henderson
wrote:

> Carey & Tom,
>
> Thanks, I've forwarded your info to him.
>
> Ken H.
>
>
> On Wed, Feb 21, 2018 at 6:12 PM, Tom McManus wrote:
>
>> What does he need Ken? Have him call me. I am on the Black List.
>>
>> --
>> Tom McManus
>> 1977 Royale
>>
>> Chesapeake VA
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
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Re: [GMCnet] Harrison Brakes [message #329403 is a reply to message #329379] Thu, 22 February 2018 09:50 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Ken, the only ones I ever saw were the set qwe took off Stick's coach on your pit a couple years back. Other than needing an 'outlaw' hub, I was impressed.

--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] Harrison Brakes [message #329418 is a reply to message #329379] Thu, 22 February 2018 16:55 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 49
Registered: November 2017
Location: Baltimore
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Member
My setup is Leigh Harrison upgrade to disk brakes on the forward rear axle with OEM drums & parking brake on the rear axle. List below compiled during my own rebuild effort this past November. I was able to get it done with no documentation from PO due in large part to contributions from members of this forum (thanks people!).

1. Rotors: Duralast 5445 (Autozone) or NAPA Premium NB 4885731/NB4885978
Fitment from 1993 (and other years) Ford F250 front rotor

2. Calipers: Cardone 18P4122 (Right) and 18P4123 (Left)
Fitment from 1984 Chevrolet C20 Pickup

3. Pads: Performance Friction 0052.20 Carbon Metallic

4. Wheel Bearings Inner: = Timken Set45 (Timken LM501310 Race & LM501349 Bearing)
Wheel Bearings Outer: = Timken 15243 Race & 15103S Bearing
Bearing Seal: Timken 8974S

Photos here: http://www.gmcmhphotos.com/photos/g7122-leigh-harrison-rear-brake-maintenance.html


Jim Wack - 1976 23' Crestmont Baltimore, Maryland

[Updated on: Thu, 22 February 2018 17:00]

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Re: [GMCnet] Harrison Brakes [message #329419 is a reply to message #329379] Thu, 22 February 2018 17:03 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
Isn't there a set of calipers one could use from a heavy duty truck that
would provide parking brake capability? I do know the Ford super duty has
four wheel disc brakes.

Sammy Williams
Thinking out loud

A water jet could cut out the mounts for them id imagine.

On Feb 22, 2018 16:56, "James Wack" wrote:

My setup is Leigh Harrison upgrade to disk brakes on the forward rear axle
with OEM drums & parking brake on the rear axle. List compiled during my
own rebuild effort this past November:

1. Rotors: Duralast 5445 (Autozone) or NAPA Premium NB 4885731/NB4885978
Fitment from 1993 (and other years) Ford F250 front rotor

2. Calipers: Cardone 18P4122 (Right) and 18P4123 (Left)
Fitment from 1984 Chevrolet C20 Pickup

3. Pads: Performance Friction 0052.20 Carbon Metallic

4. Wheel Bearings Inner: = Timken Set45 (Timken LM501310 Race & LM501349
Bearing)
Wheel Bearings Outer: = Timken 15243 Race & 15103S Bearing
Bearing Seal: Timken 8974S

Photos here: http://www.gmcmhphotos.com/photos/g7122-leigh-harrison-
rear-brake-maintenance.html
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland

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Re: [GMCnet] Harrison Brakes [message #329426 is a reply to message #329419] Thu, 22 February 2018 20:35 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
James,

From your photos and the part numbers supplies I believe the calipers you used are what is referred to as 80mm. According to TSM the
pistons are actually 3 1/32in or 76.9938mm.

http://www.tsmmfg.com/More.../3020.html

I have them on the front and middle wheels of Double Trouble; however, I have the Caddy caliper mounting plates and smaller rotors
on the middle wheels as per:

http://www.gmcmhphotos.com/photos/g3119-cadilac-disk-brakes.html

Sammy,

Yes, there are calipers with built in parking brakes:

1) 2 1/32in piston = 51.5938mm http://www.tsmmfg.com/More.../3110.html

2) 2 13/32in piston = 61.1188mm http://www.tsmmfg.com/More.../3120.html

3) 2 1/32in piston = 61.1188mm http://www.tsmmfg.com/More.../3121.html

However, GMC "folklore" notes these calipers can cause problems if they are not maintained properly as the parking brake function
will not release.

BTW you can find all these calipers on RockAuto for a hell of a lot less than the major auto parts chains or TSM.

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 Wack
Sent: Friday, February 23, 2018 9:55 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Harrison Brakes

My setup is Leigh Harrison upgrade to disk brakes on the forward rear axle with OEM drums & parking brake on the rear axle. List
compiled during my own rebuild effort this past November:

1. Rotors: Duralast 5445 (Autozone) or NAPA Premium NB 4885731/NB4885978
Fitment from 1993 (and other years) Ford F250 front rotor

2. Calipers: Cardone 18P4122 (Right) and 18P4123 (Left)
Fitment from 1984 Chevrolet C20 Pickup

3. Pads: Performance Friction 0052.20 Carbon Metallic

4. Wheel Bearings Inner: = Timken Set45 (Timken LM501310 Race & LM501349 Bearing)
Wheel Bearings Outer: = Timken 15243 Race & 15103S Bearing
Bearing Seal: Timken 8974S

Photos here: http://www.gmcmhphotos.com/photos/g7122-leigh-harrison-rear-brake-maintenance.html
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland

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 Sammy Williams
Sent: Friday, February 23, 2018 10:04 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Harrison Brakes

Isn't there a set of calipers one could use from a heavy duty truck that
would provide parking brake capability? I do know the Ford super duty has
four wheel disc brakes.

Sammy Williams
Thinking out loud



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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
Re: [GMCnet] Harrison Brakes [message #329436 is a reply to message #329426] Fri, 23 February 2018 11:26 Go to previous messageGo to next message
Wackster is currently offline  Wackster   United States
Messages: 49
Registered: November 2017
Location: Baltimore
Karma: 0
Member
Hello Rob,

I believe you correct about my Leigh Harrison brakes using "80mm" calipers. The various GMC references to 80mm calipers added to my confusion during the rebuild effort due to the piston diameter measuring somewhat less. Did my best to match what I was replacing. Thanks for the links to your brake photos. BTW, what is the function of the cable and spring return bracket assembly that I see on your rear bogey?


Jim Wack - 1976 23' Crestmont Baltimore, Maryland
Re: [GMCnet] Harrison Brakes [message #329449 is a reply to message #329436] Fri, 23 February 2018 17:01 Go to previous message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
James,

Those photos are not mine, they are John Wrights.

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 Wack
Sent: Saturday, February 24, 2018 4:26 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Harrison Brakes

Hello Rob,

I believe you correct about my Leigh Harrison brakes using "80mm" calipers. The various GMC references to 80mm calipers added to my
confusion during
the rebuild effort due to the piston diameter measuring somewhat less. Did my best to match what I was replacing. Thanks for the
links to your brake
photos. BTW, what is the function of the cable and spring return bracket assembly that I see on your rear bogey?
--
Wackster - 1976 23' Crestmont
Baltimore, Maryland



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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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