GM Volt Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
659 Posts
Discussion Starter · #1 ·
Would like to see:

2 Year Brake fluid changes as brake fluid is Hydroscopic (Absorbs water leading to boiling sooner in harsh conditions and corrosion of braking components).
As it's DOT 3 fluid - it doesn't last for the life of the vehicle!

Full procedures for replacing coolant & bleeding air out of Engine / ICE / Power / Battery.
In an emergency & away from a GM dealer it would be great to know.

Regards,

Martin
 

·
Registered
Joined
·
5,431 Posts
Wait a few more years, then look for the Haynes Service Manual set for the Volt. I have the Haynes manuals and the original GM factory service manuals for all my GM cars, and the Haynes manual is easier to understand. The home web page is http://www.haynes.com so take a look for your present vehicles or buy it at local auto shops.

If you wish to see their catalog online (and turn pages!), try this link: http://digital.turn-page.com/title/5545

Page 6 covers the GM line.

Raymond

P.S. I almost forgot that Haynes also covers home computers: http://www.haynes.com/products/sfID1/115/sfID2/124
 

·
Registered
Joined
·
733 Posts
I have over 1800 miles on my Volt. Just 97 on gasoline. Total driving time of 7 weeks. My oil life indicates 93% remaining. Looks like Volt #555 will need an oil change each January. Only 2.2 gallons of gasoline used so far. Total cost for gas $8.80 (dealer gasoline).
 

·
Registered
Joined
·
4,728 Posts
Would like to see:

2 Year Brake fluid changes as brake fluid is Hydroscopic (Absorbs water leading to boiling sooner in harsh conditions and corrosion of braking components).
As it's DOT 3 fluid - it doesn't last for the life of the vehicle!

Full procedures for replacing coolant & bleeding air out of Engine / ICE / Power / Battery.
In an emergency & away from a GM dealer it would be great to know.

Regards,

Martin
Hi Martin

I think you probably meant hygroscopic, which is the tendency for something (in this case a fluid) to absorb water.
Yes, DOT3 brake fluids are hygroscopic in nature so care must be taken to limit potential moisture intrusion. A well sealed system with externally viewable levels in the reservoir is the first step. So it's important that the lid on your brake fluid reservoir remain secure at all times and should NOT be routinely removed for "fluid inspections" as there's really nothing to see that you cant observe from the external "sight" level.

Additionally GM's Delco Supreme II DOT3 compatible brake fluid (recommended in the owners manual for ALL GM products) contains enhanced corrosion inhibitors and additives to prevent premature wear and retains its boiling point properties much longer than conventional DOT 3 brake fluids and as such is the factory fill on all General Motors products.

At one time, a known entry point for moisture (and air) to leach into the system was the rubber hoses used on many fluid connections to the calipers or on chassis to axle lines (necessary due to suspension travel) However since the mid 90's on General Motors vehicles (and many other OEMs) the addition of new specialized ethylene-propylene (EPM/EPDM) rubbers used in the construction of these hoses and seals has dramatically reduced this effect as well as the fluid "stripping" of the rubber's internal surfaces that eventually turns the fluid dark and accelerates the critical contamination point.

Actually there's no supporting evidence that frequent brake fluid changes actually in any way prevents the eventual necessity to replace rubber components like master cylinder and caliper piston seals or wheel cylinder seals. These are typically a rubber to metal interface and the rubber eventually wears to the point that there's a brake performance issue. This WILL occur at some point in time, whether you change your brake fluid religiously or not. Service data from various industry sources just doesn't seem to indicate that frequent fluid replacement is detrimental to to this event horizon. If the manufacturer's own maintenance requires fluid changes, then I guess they have their own reaons for this and their recommendation should be followed. But when these types of brake sytem repairs are performed the old fluid is essentially expunged during the bleeding process.

While I won't dispute regular brake fluid changes might give "peace of mind", it has also been noted that used brake fluids are quite toxic and represent significant environmental hazard and unfortunately are often disposed of incorrectly.But someone somewhere still has to deal with the disposal of these contaminated maintenance fluids (including engine oils and coolants) so General Motors has been doing a TON of research and development in order to minimize the environmental impact (and owner borne costs) of automotive fluid maintenance. Hence the development of longer-life coolants and other fluids, the creation of new oil longevity standards such as Dexos, and the elimination of time-based oil maintenance schedules in favor of usage based algorithms and oil wear indexes built into the GM oil-life monitoring system.

So you see there's nothing that really need s to be done here, however if you decide to have your brake fluid replaced more often than outlined in the Volt maintenance schedule it is also recommended that you have this service performed by a GM dealer to insure the correct fluids, tools, and technician skill-sets are present to insure it's success. There's a wee bit more to this on the Volt due to the slip-control boost braking system and as such even requires electronic equipment (laptop w/GDS and MDI vehicle interface) to perform successfully.

HTH
WopOnTour
 

·
Registered
Joined
·
4,728 Posts
Oh and the Volt's numerous coolant systems also use specific long-life coolants and require a "vacuum" type fluid replacement tool that all dealers have (and most competitive shops as well). There is also a correct process/sequence that MUST be followed in order to do this and prevent possible air cavitation or entrapment that could result in critical components over-heating. (Li-Ion battery, HV heaters, pumps, electronic controls, ICE etc)
This information is available in the Volt's service/repair data that would also be obtainable via on-line subscription by any progressive automotive shop that's on top of things. It is not recommended these services be performed by anyone other than a trained service professional.
WOT
 

·
Registered
Joined
·
659 Posts
Discussion Starter · #6 ·
Hi Martin

I think you probably meant hygroscopic, which is the tendency for something (in this case a fluid) to absorb water.
Yes, DOT3 brake fluids are hygroscopic in nature so care must be taken to limit potential moisture intrusion. A well sealed system with externally viewable levels in the reservoir is the first step. So it's important that the lid on your brake fluid reservoir remain secure at all times and should NOT be routinely removed for "fluid inspections" as there's really nothing to see that you cant observe from the external "sight" level.

Additionally GM's Delco Supreme II DOT3 compatible brake fluid (recommended in the owners manual for ALL GM products) contains enhanced corrosion inhibitors and additives to prevent premature wear and retains its boiling point properties much longer than conventional DOT 3 brake fluids and as such is the factory fill on all General Motors products.

At one time, a known entry point for moisture (and air) to leach into the system was the rubber hoses used on many fluid connections to the calipers or on chassis to axle lines (necessary due to suspension travel) However since the mid 90's on General Motors vehicles (and many other OEMs) the addition of new specialized ethylene-propylene (EPM/EPDM) rubbers used in the construction of these hoses and seals has dramatically reduced this effect as well as the fluid "stripping" of the rubber's internal surfaces that eventually turns the fluid dark and accelerates the critical contamination point.

Actually there's no supporting evidence that frequent brake fluid changes actually in any way prevents the eventual necessity to replace rubber components like master cylinder and caliper piston seals or wheel cylinder seals. These are typically a rubber to metal interface and the rubber eventually wears to the point that there's a brake performance issue. This WILL occur at some point in time, whether you change your brake fluid religiously or not. Service data from various industry sources just doesn't seem to indicate that frequent fluid replacement is detrimental to to this event horizon. If the manufacturer's own maintenance requires fluid changes, then I guess they have their own reaons for this and their recommendation should be followed. But when these types of brake sytem repairs are performed the old fluid is essentially expunged during the bleeding process.

While I won't dispute regular brake fluid changes might give "peace of mind", it has also been noted that used brake fluids are quite toxic and represent significant environmental hazard and unfortunately are often disposed of incorrectly.But someone somewhere still has to deal with the disposal of these contaminated maintenance fluids (including engine oils and coolants) so General Motors has been doing a TON of research and development in order to minimize the environmental impact (and owner borne costs) of automotive fluid maintenance. Hence the development of longer-life coolants and other fluids, the creation of new oil longevity standards such as Dexos, and the elimination of time-based oil maintenance schedules in favor of usage based algorithms and oil wear indexes built into the GM oil-life monitoring system.

So you see there's nothing that really need s to be done here, however if you decide to have your brake fluid replaced more often than outlined in the Volt maintenance schedule it is also recommended that you have this service performed by a GM dealer to insure the correct fluids, tools, and technician skill-sets are present to insure it's success. There's a wee bit more to this on the Volt due to the slip-control boost braking system and as such even requires electronic equipment (laptop w/GDS and MDI vehicle interface) to perform successfully.

HTH
WopOnTour
Cheers HTH for a very detailed & informative article,

I personally still believe that a change of fluid every 2-4 years would help brake components minimise wear as you are flushing out the worn materials.
I have done this on a 9 year old ABS equipped GM product every two years and never needed their special GM computers - why the ABS cycles every time you start your car so between changes it's mixed in newer brake fluid.
I keep everything surgery clean (no dust /dirt) and have a Mitvac vacuum bleeder at the brakes, if you never let air in by over draining the brake fluid reservoir then no problem.

I know of fellow car owners who never changed their brake fluid and they now have an impressive list of expensive brake components compared to mine with only regular items. So yes the GM brake fluid is great but so is changing it, yes I know - the environment but which is worse -brake fluid or the resources required to manufacture / remanufacture new ABS modules etc. etc.

Good to know that things have improved with brake fluid longetivty as repair shops charge for everything - but is it really done? This is only discovered at another repair shop or as a major defect.
Lately more consumers are unfortunately not mechanically minded car people.

Interesting the changes GM have made as Silicon type brake fluid used in race applications never made it for various reasons to normal road use. So well done to them!

Martin
 

·
Registered
Joined
·
659 Posts
Discussion Starter · #7 ·
Hi WOT,

Thanks once again, but the question is do you "trust" the mechanic at the dealership.....
Only if I'm standing next to them .... which is not allowed anymore due to OH&S issues even if you have been around dangerous machinery in your working carrier.
So until dealers become "transparent" I prefer to do everything myself even if costs in special tools and takes me 3 times longer,
Why - cause I know it's done right and was actually done!

You can tell i've got issues - but being burnt before makes you learn the hardway $$$!

Thanks,

Martin
 
1 - 7 of 7 Posts
Top