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[GMCnet] DOT 5 Maintenance ? [message #155682] Fri, 06 January 2012 08:33 Go to next message
Beach Coach is currently offline  Beach Coach   United States
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Registered: December 2011
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Member
I need advice on how to maintain my GMC braking system that uses DOT 5
brake fluid? For the last two years I have just been topping up the
reservoir before each trip.

Hugh MacDougall
Nova Scotia
1978 Palm Beach
1977 Transmode




.
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hugh MacDougall Antigonish, Nova Scotia 1975 Eleganza II
Re: [GMCnet] DOT 5 Maintenance ? [message #155683 is a reply to message #155682] Fri, 06 January 2012 08:43 Go to previous messageGo to next message
GeorgeRud is currently offline  GeorgeRud   United States
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Though it shouldn't have the moisture absorbing problems of other brake fluids, I think it still should be periodically bled like you would any other fluid.

I also am using DOT5 in my coach. We went to it when we rebuilt the brake system, and it seems to be working nicely so far. There are pros and cons to this approach, but we figured to give it a try, and so far the coach stops great without any sponginess to the brake pedal. Time will tell if this was a good idea or not!


George Rudawsky
Chicago, IL
75 Palm Beach
Re: [GMCnet] DOT 5 Maintenance ? [message #155696 is a reply to message #155683] Fri, 06 January 2012 10:12 Go to previous messageGo to next message
Beach Coach is currently offline  Beach Coach   United States
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Thanks George,

I am going to bleed the brakes in April before we get going for the summer
season. I haven't had any braking problems and I am quite comfortable with
the braking performance.

Hugh MacDougall
Nova Scotia
1978 Palm Beach
1977 Transmode

On Fri, Jan 6, 2012 at 10:43 AM, George Rudawsky <GeorgeRud@aol.com> wrote:

>
>
> Though it shouldn't have the moisture absorbing problems of other brake
> fluids, I think it still should be periodically bled like you would any
> other fluid.
>
> I also am using DOT5 in my coach. We went to it when we rebuilt the brake
> system, and it seems to be working nicely so far. There are pros and cons
> to this approach, but we figured to give it a try, and so far the coach
> stops great without any sponginess to the brake pedal. Time will tell if
> this was a good idea or not!
> --
> George Rudawsky
> Chicago, IL
> 75 Palm Beach
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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hugh MacDougall Antigonish, Nova Scotia 1975 Eleganza II
Re: [GMCnet] DOT 5 Maintenance ? [message #155707 is a reply to message #155683] Fri, 06 January 2012 12:37 Go to previous messageGo to next message
Greg and April is currently offline  Greg and April   United States
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What are the pro's and con's?
.

Greg H.

I don't just march to the beat of my own drum - I have an entire brass band
to keep me company.

.
----- Original Message -----
From: "George Rudawsky" <GeorgeRud@aol.com>
To: <gmclist@temp.gmcnet.org>
Sent: Friday, January 06, 2012 7:43
Subject: Re: [GMCnet] DOT 5 Maintenance ?


>
>
> I also am using DOT5 in my coach. We went to it when we rebuilt the brake
> system, and it seems to be working nicely so far. There are pros and cons
> to this approach, but we figured to give it a try, and so far the coach
> stops great without any sponginess to the brake pedal. Time will tell if
> this was a good idea or not!
> --

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Re: [GMCnet] DOT 5 Maintenance ? [message #155708 is a reply to message #155707] Fri, 06 January 2012 13:26 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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One Con. You cannot mix DOT 3/4 with DOT 5. Even an accidental mix will result in you needing a complete brake teardown. Replacing everything in the brake system is the only solution that I have discovered to get rid of the DOT 5 and replacing it with DOT 3/4.
Yes, P.O. put DOT 5 in my current coach.Tom,
MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] DOT 5 Maintenance ? [message #155721 is a reply to message #155682] Fri, 06 January 2012 14:16 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Hugh,

Here's some basic information that I've read in articles I've found by doing Google searches on brake fluids.

Dot 3 and Dot 4 are hydroscopic (they absorb water) Dot 5 is hydrophobic (doesn't absorb water). However, you can still have water
problems in brake systems that use Dot 5 as water can still get in. It accumulates in "slugs," they can freeze and block lines.

Therefore one should flush the system every so often.

"They" say one should flush a Dot 3 or Dot 4 filled system every couple of years. I am loathe to make a recommendation as to the
time period between flushes simply because it would be an opinion with absolutely no basis in fact or research. If you wound up
having a brake system problem based on my recommendation I'd feel responsible!

I would suggest you do a Google search, read, and evaluate the information provided and go from there.

Regards,
Rob M.

-----Original Message-----
From: Beach Coach

I need advice on how to maintain my GMC braking system that uses DOT 5
brake fluid? For the last two years I have just been topping up the
reservoir before each trip.

Hugh MacDougall
Nova Scotia
1978 Palm Beach
1977 Transmode

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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] DOT 5 Maintenance ? [message #155739 is a reply to message #155682] Fri, 06 January 2012 17:34 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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The price of DOT 3 and 4 is so cheap compared to bottled water and gasoline and compared to the price of brake components, that its cheap insurance. If nothing else, turkey baster the stuff out of the MC yearly and refill for about $1. This keeps the fluid that is most exposed to air (moisture) fresh and the MC rubber parts from being attacked by rancid fluid. If you run a Powermaster this is especially true as the bad fluid attacks the rubber checkvalve so that the pump runs too much and burns out, and the internal accumulator seal fails loosing nitrogen charge. All for about $1.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] DOT 5 Maintenance ? [message #155753 is a reply to message #155721] Fri, 06 January 2012 18:38 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
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So, if I live in a relative low humidity area I would use the Dot 3/4
product, but if I live in a high humid area than I would use the Dot 5?

On Fri, Jan 6, 2012 at 1:16 PM, Rob Mueller <robmueller@iinet.net.au> wrote:

> Hugh,
>
> Here's some basic information that I've read in articles I've found by
> doing Google searches on brake fluids.
>
> Dot 3 and Dot 4 are hydroscopic (they absorb water) Dot 5 is hydrophobic
> (doesn't absorb water). However, you can still have water
> problems in brake systems that use Dot 5 as water can still get in. It
> accumulates in "slugs," they can freeze and block lines.
>
> Therefore one should flush the system every so often.
>
> "They" say one should flush a Dot 3 or Dot 4 filled system every couple of
> years. I am loathe to make a recommendation as to the
> time period between flushes simply because it would be an opinion with
> absolutely no basis in fact or research. If you wound up
> having a brake system problem based on my recommendation I'd feel
> responsible!
>
> I would suggest you do a Google search, read, and evaluate the information
> provided and go from there.
>
> Regards,
> Rob M.
>
> -----Original Message-----
> From: Beach Coach
>
> I need advice on how to maintain my GMC braking system that uses DOT 5
> brake fluid? For the last two years I have just been topping up the
> reservoir before each trip.
>
> Hugh MacDougall
> Nova Scotia
> 1978 Palm Beach
> 1977 Transmode
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Bruce Hart
GMC Wannabe
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: [GMCnet] DOT 5 Maintenance ? [message #155756 is a reply to message #155753] Fri, 06 January 2012 18:46 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Senior Member
Probably best to use the Factory Recommended Brake fluid. DOT 3. Change it
by pressure bleeding every 2 years in wet/humid climates with extreme
temperature changes. In arid climates that have nearly constant humidity
and little rain, you can go as much as 5 years. Use colored brake fluid to
flush with, and when you see a color change at the bleeders, you are good
to go. This maintence step will go a long way towards limiting the amount
of brake problems yoy have that are water related. Just my opinion based on
factory training and practical experience with brakes. It is what I do with
my own coach.
Jim Hupy
Salem, OR
78 GMC Royale 403

On Fri, Jan 6, 2012 at 4:38 PM, Bruce Hart <hartsgmc@gmail.com> wrote:

> So, if I live in a relative low humidity area I would use the Dot 3/4
> product, but if I live in a high humid area than I would use the Dot 5?
>
> On Fri, Jan 6, 2012 at 1:16 PM, Rob Mueller <robmueller@iinet.net.au>
> wrote:
>
> > Hugh,
> >
> > Here's some basic information that I've read in articles I've found by
> > doing Google searches on brake fluids.
> >
> > Dot 3 and Dot 4 are hydroscopic (they absorb water) Dot 5 is hydrophobic
> > (doesn't absorb water). However, you can still have water
> > problems in brake systems that use Dot 5 as water can still get in. It
> > accumulates in "slugs," they can freeze and block lines.
> >
> > Therefore one should flush the system every so often.
> >
> > "They" say one should flush a Dot 3 or Dot 4 filled system every couple
> of
> > years. I am loathe to make a recommendation as to the
> > time period between flushes simply because it would be an opinion with
> > absolutely no basis in fact or research. If you wound up
> > having a brake system problem based on my recommendation I'd feel
> > responsible!
> >
> > I would suggest you do a Google search, read, and evaluate the
> information
> > provided and go from there.
> >
> > Regards,
> > Rob M.
> >
> > -----Original Message-----
> > From: Beach Coach
> >
> > I need advice on how to maintain my GMC braking system that uses DOT 5
> > brake fluid? For the last two years I have just been topping up the
> > reservoir before each trip.
> >
> > Hugh MacDougall
> > Nova Scotia
> > 1978 Palm Beach
> > 1977 Transmode
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
>
>
>
> --
> Bruce Hart
> GMC Wannabe
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Re: [GMCnet] DOT 5 Maintenance ? [message #155757 is a reply to message #155753] Fri, 06 January 2012 18:59 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Bruce,

Not really, if you live in a high humididity ;-) area you would flush the system more frequently no matter what type of fluid you
used.

Here's a link to some info I just posted to the photo site:

http://www.gmcmhphotos.com/photos/showphoto.php?photo=41972

As you can see from the photo ATE notes that you can leave their fluid in a vehicle up to three years. If you change it every other
year I reckon that would be mo betta!

Regards,
Rob M.

-----Original Message-----
From: Bruce Hart

So, if I live in a relative low humidity area I would use the Dot 3/4
product, but if I live in a high humid area than I would use the Dot 5?

Bruce Hart
GMC Wannabe

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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] DOT 5 Maintenance ? [message #155777 is a reply to message #155682] Fri, 06 January 2012 21:22 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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Beach Coach wrote on Fri, 06 January 2012 08:33

I need advice on how to maintain my GMC braking system that uses DOT 5
brake fluid? For the last two years I have just been topping up the
reservoir before each trip.




The DOT5 has a tendency to absorb air. Harley used to use DOT5 (supposedly as it didn't damage the paint) and every trip I took over the western mountain passes I would lose the brakes until I started flushing the system before I went west. I have converted my '75 Corvette to DOT5 many years ago with no problems, and no periodic flushing, however it has never been over the high western passes. It will be flushed if it ever goes west.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] DOT 5 Maintenance ? [message #155816 is a reply to message #155682] Sat, 07 January 2012 08:44 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Beach Coach wrote on Fri, 06 January 2012 09:33

I need advice on how to maintain my GMC braking system that uses DOT 5 brake fluid? For the last two years I have just been topping up the reservoir before each trip.

Hugh MacDougall
Nova Scotia
1978 Palm Beach
1977 Transmode

Hugh,

Anyplace in the Maritimes, spring is wet. The reported problem with DOT5 is that moisture actually gets into the fluid in the cylinders and calipers by getting part the seals.

My suggestion would be to flush the system sometime, and if any water comes out, then plan to flush the system on a regular basis. Otherwise, leave it alone.

Water is not at all miscible with DOT5, so if there is any there, it should be visible.

I had a Jeep pickup for 15 of it's 30 years. The brakes were gone when I got it and I replaced everything but the drums. I was advised by classic car owning friends to use DOT5. I put DOT5 with the all new parts. I heard about this water problem when the truck had about 10 years on the new brakes and flushed the system. I found no evidence of water.

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] DOT 5 Maintenance ? [message #155839 is a reply to message #155682] Sat, 07 January 2012 16:11 Go to previous messageGo to next message
GeorgeRud is currently offline  GeorgeRud   United States
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My conversion to DOT5 was also done after the brake system was apart and mostly replaced. I also have a few classic car owning friends, and the DOT5 seems to be their fluid of choice.

If you're doing fine with DOT3 or 4, and are flushing the system as recommended, I don't know that I would go through all the work involved to switch to DOT5. Using the colored brake fluids (like the ATE ones) does make it easier to know when the system is fully flushed.


George Rudawsky
Chicago, IL
75 Palm Beach
Re: [GMCnet] DOT 5 Maintenance ? [message #155841 is a reply to message #155839] Sat, 07 January 2012 16:23 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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George,

Very good point!

After "ALL THE WORK" add "AND COST"

Regards,
Rob M.


-----Original Message-----
From: George Rudawsky

My conversion to DOT5 was also done after the brake system was apart and mostly replaced. I also have a few classic car owning
friends, and the DOT5 seems to be their fluid of choice.

IF YOU'RE DOING FINE WITH DOT3 OR 4, AND ARE FLUSHING THE SYSTEM AS RECOMMENDED, I DON'T KNOW THAT I WOULD GO THROUGH ALL THE WORK
INVOLVED TO SWITCH TO DOT5.

Using the colored brake fluids (like the ATE ones) does make it easier to know when the system is fully flushed.
--
George

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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] DOT 5 Maintenance ? [message #155857 is a reply to message #155841] Sat, 07 January 2012 19:59 Go to previous messageGo to next message
Bob de Kruyff   United States
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I wonder what the OEM's use and why???

Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] DOT 5 Maintenance ? [message #155872 is a reply to message #155682] Sat, 07 January 2012 21:44 Go to previous message
GeorgeRud is currently offline  GeorgeRud   United States
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I would imagine the answers would be DOT4 fluid and cost.

George Rudawsky
Chicago, IL
75 Palm Beach
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