i heard someone say salt doesn't damage a vehicle until it gets above freezing, is there any truth to this?
when does salt become a problem
- Thread starter swirlparanoid
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When its wet, so yeah around the freezing mark. The wetness helps it become the electrolyte. Salt also absorbs water from the air so if it's really dank and humid it turns that dark grey.
Parking in garages with cold concrete floors causes localized humidity spikes under the undercarriage. Sometimes I go weeks without my garage fully drying out from all the "car water". (But wife loves not having frost on her ride & that counts for something.
)
IMO highway driven cars get it worse, I can't figure out if it's the calcium chloride or brine pretreat or the high velocity tire splatter from other vehicles, but "highway driven" isn't that big a positive up here.
Warm water gets salt off way better than cool, but go too hot and you shock the paint.
Parking in garages with cold concrete floors causes localized humidity spikes under the undercarriage. Sometimes I go weeks without my garage fully drying out from all the "car water". (But wife loves not having frost on her ride & that counts for something.
IMO highway driven cars get it worse, I can't figure out if it's the calcium chloride or brine pretreat or the high velocity tire splatter from other vehicles, but "highway driven" isn't that big a positive up here.
Warm water gets salt off way better than cool, but go too hot and you shock the paint.
I'm pretty sure rust can form below 0C but it does work faster at higher temperatures. A saturated salt solution still freezes at -22C so maybe below that, then salt and rust is "sleeping" in spite of what Neil Young says.
another question i had was if spraying with water frequently is a good idea, i would think it would just blast salty water into the nooks and cranny's or am i wrong
Any time it's wet (it doesn't need to be as warm as freezing - the whole reason salt is applied is to keep water liquid below freezing) corrosion can be taking place. The rate of corrosion increases with temperature.
It's actually very important to make sure you thoroughly clean the salt off of your winter wide when spring returns otherwise salt hidden away will work VERY fast when warm and wet in the summer. Underbody washing, removing wheel well liners to clean buildup of salty grit from hidden areas etc... is the best way to be sure.
As already said, heated garages can really rust out a winter car that sees salt.
It's actually very important to make sure you thoroughly clean the salt off of your winter wide when spring returns otherwise salt hidden away will work VERY fast when warm and wet in the summer. Underbody washing, removing wheel well liners to clean buildup of salty grit from hidden areas etc... is the best way to be sure.
As already said, heated garages can really rust out a winter car that sees salt.
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Salt is a problem when you drive through it, and it gets wet. As long as it is wet it is a problem!
Kestas
Staff member
Some communities spike their salt with calcium chloride, which is effective at deicing down to -60°F. With two chlorine ions, this salt is extremely corrosive.
Keep your car outside during the winter, it will thank you.
Heated garage is a no-no for me for winter months. So bad for the body, etc.
Heated garage is a no-no for me for winter months. So bad for the body, etc.
Salt is a problem when it is put on the road,melts ice though.
I don't buy keeping a car in the garage causes rust faster one bit. My cars and trucks are always garaged and my oldest one is over 22 years old and is 100% rust free. None of my cars have any rust at all including one that is a beater and NEVER gets cleaned or washed and it is rust free and it has seen a lot of winter roads. It gets cleaned in the spring rains. It's a 1989 Chevey S-10 and even the bottom inside edge of the doors are free of rust. The Volvos, Camaro, and Tahoe get a fresh water rince after every snow storm which helps keep the salt off.
Originally Posted By: Chris B.
I don't buy keeping a car in the garage causes rust faster one bit. My cars and trucks are always garaged and my oldest one is over 22 years old and is 100% rust free. None of my cars have any rust at all including one that is a beater and NEVER gets cleaned or washed and it is rust free and it has seen a lot of winter roads. It gets cleaned in the spring rains. It's a 1989 Chevey S-10 and even the bottom inside edge of the doors are free of rust. The Volvos, Camaro, and Tahoe get a fresh water rince after every snow storm which helps keep the salt off.
It is a HEATED garage, or just a garage?
I don't buy keeping a car in the garage causes rust faster one bit. My cars and trucks are always garaged and my oldest one is over 22 years old and is 100% rust free. None of my cars have any rust at all including one that is a beater and NEVER gets cleaned or washed and it is rust free and it has seen a lot of winter roads. It gets cleaned in the spring rains. It's a 1989 Chevey S-10 and even the bottom inside edge of the doors are free of rust. The Volvos, Camaro, and Tahoe get a fresh water rince after every snow storm which helps keep the salt off.
It is a HEATED garage, or just a garage?
Originally Posted By: Craig in Canada
Originally Posted By: Chris B.
I don't buy keeping a car in the garage causes rust faster one bit. My cars and trucks are always garaged and my oldest one is over 22 years old and is 100% rust free. None of my cars have any rust at all including one that is a beater and NEVER gets cleaned or washed and it is rust free and it has seen a lot of winter roads. It gets cleaned in the spring rains. It's a 1989 Chevey S-10 and even the bottom inside edge of the doors are free of rust. The Volvos, Camaro, and Tahoe get a fresh water rince after every snow storm which helps keep the salt off.
It is a HEATED garage, or just a garage?
Just a garage. It stays warm enough that water does not freeze though.
Originally Posted By: Chris B.
I don't buy keeping a car in the garage causes rust faster one bit. My cars and trucks are always garaged and my oldest one is over 22 years old and is 100% rust free. None of my cars have any rust at all including one that is a beater and NEVER gets cleaned or washed and it is rust free and it has seen a lot of winter roads. It gets cleaned in the spring rains. It's a 1989 Chevey S-10 and even the bottom inside edge of the doors are free of rust. The Volvos, Camaro, and Tahoe get a fresh water rince after every snow storm which helps keep the salt off.
It is a HEATED garage, or just a garage?
Just a garage. It stays warm enough that water does not freeze though.
It's moisture that is the catalyst( changing it from an inert substance) for salt not heat
Road Salt
Although dry salt is inert 15 – 20.oF (9 – 29.oC) is considered the lower limit for salt to melt snow and ice but once H2O, even in the form of moist air (i.e. humidity) is added the freezing point is lowered and the sprayed brine solution (pH 8.5) used on roads will have an adverse effect (the formation of rust and/or corrosion) on the vehicles paint and undercarriage.
When washing the vehicle ensure that all salt removed to avoid a brine solution remaining on the paint finish. Using a durable protection (Collinite Insulator Wax) will provide a sacrificial and renewable protection to the vehicles paint finish.
The salts (salt CI and water H2O produce oxides, which cause corrosion) used for freezing point depression in a sprayed brine solution (often mixed with grit / sand for tyre adhesion) commonly used are;
(a) Sodium chloride (NaCl) the most common salt used Sodium chloride (rock salt, halite) Calcium chloride is thought to be more environmentally friendly than sodium chloride when used to de-ice roads, however a drawback is that it tends to promote corrosion (of vehicles) more so than sodium chloride. NaCl is also more readily available and does not have any special handling or storage requirements, unlike calcium chloride. Lowest practical temp: 15.oF (9°.C) keeps sidewalks dry, corrosive, damages to concrete and vegetation
(b) Calcium chloride
(CaCl2) works at lower temperatures(than sodium chloride. Calcium chloride is preferred over sodium chloride, since it releases energy upon forming a solution with water; heating any ice or snow it is in contact with. It also lowers the freezing point, depending on the concentration. Lowest practical temp: 20.o F (29. °C) melts ice faster than sodium chloride, attracts moisture, surfaces slippery below
(c) Magnesium chloride
(MgCl2) is the name for the chemical compounds and its various hydrates MgCl2 (H2O) x. These salts are typical ionic halides, being highly soluble in water. Melts ice faster than sodium chloride. Lowest practical temp: 5. °F (15°.C) attracts moisture
Magnesium chloride is very effective even at the lowest temperatures but also contains the most aggressive corrosives (especially on glass surfaces) and a sprayed brine solution, it is used to prevent snow / ice adhesion to the road surface.
A number of state highway departments throughout the United States have decreased the use of rock salt and sand on roadways and have increased the use of solutions of magnesium chloride (often called "liquid magnesium chloride") as a de-icer. Magnesium chloride is much less toxic to plant life surrounding highways and airports, and is less corrosive to concrete and steel (and other iron alloys) than sodium chloride.
Anti-icing liquids, which according to State authorities, the liquid solution consists of - Magnesium chloride (MgCl2) Calcium chloride (CaCl2) and other liquids that work like anti-freeze, by lowering the freezing temperature of water and preventing ice from forming a strong bond to the road
Road Salt
Although dry salt is inert 15 – 20.oF (9 – 29.oC) is considered the lower limit for salt to melt snow and ice but once H2O, even in the form of moist air (i.e. humidity) is added the freezing point is lowered and the sprayed brine solution (pH 8.5) used on roads will have an adverse effect (the formation of rust and/or corrosion) on the vehicles paint and undercarriage.
When washing the vehicle ensure that all salt removed to avoid a brine solution remaining on the paint finish. Using a durable protection (Collinite Insulator Wax) will provide a sacrificial and renewable protection to the vehicles paint finish.
The salts (salt CI and water H2O produce oxides, which cause corrosion) used for freezing point depression in a sprayed brine solution (often mixed with grit / sand for tyre adhesion) commonly used are;
(a) Sodium chloride (NaCl) the most common salt used Sodium chloride (rock salt, halite) Calcium chloride is thought to be more environmentally friendly than sodium chloride when used to de-ice roads, however a drawback is that it tends to promote corrosion (of vehicles) more so than sodium chloride. NaCl is also more readily available and does not have any special handling or storage requirements, unlike calcium chloride. Lowest practical temp: 15.oF (9°.C) keeps sidewalks dry, corrosive, damages to concrete and vegetation
(b) Calcium chloride
(CaCl2) works at lower temperatures(than sodium chloride. Calcium chloride is preferred over sodium chloride, since it releases energy upon forming a solution with water; heating any ice or snow it is in contact with. It also lowers the freezing point, depending on the concentration. Lowest practical temp: 20.o F (29. °C) melts ice faster than sodium chloride, attracts moisture, surfaces slippery below
(c) Magnesium chloride
(MgCl2) is the name for the chemical compounds and its various hydrates MgCl2 (H2O) x. These salts are typical ionic halides, being highly soluble in water. Melts ice faster than sodium chloride. Lowest practical temp: 5. °F (15°.C) attracts moisture
Magnesium chloride is very effective even at the lowest temperatures but also contains the most aggressive corrosives (especially on glass surfaces) and a sprayed brine solution, it is used to prevent snow / ice adhesion to the road surface.
A number of state highway departments throughout the United States have decreased the use of rock salt and sand on roadways and have increased the use of solutions of magnesium chloride (often called "liquid magnesium chloride") as a de-icer. Magnesium chloride is much less toxic to plant life surrounding highways and airports, and is less corrosive to concrete and steel (and other iron alloys) than sodium chloride.
Anti-icing liquids, which according to State authorities, the liquid solution consists of - Magnesium chloride (MgCl2) Calcium chloride (CaCl2) and other liquids that work like anti-freeze, by lowering the freezing temperature of water and preventing ice from forming a strong bond to the road
I must agree on this one Craig but in spring make sure all your drain holes are cleared of [censored] as they tend to trap salt etc.too..i remembered a while back when i pulled off a inside door panel and discovered dried salt stains below and seen my drain holes were plugged up..ya before winter its important to be sure to clear this hiding spot or you will see some rust starting out in the future
Originally Posted By: Hemi426
Do any of your states treat the major roads with a brine water solution before they salt like PennDot does here? That stuff REALLY makes your car rust at any temperature.
Around here it's mostly the turnpike, or at least they can afford to spray way more than anyone else.
Do any of your states treat the major roads with a brine water solution before they salt like PennDot does here? That stuff REALLY makes your car rust at any temperature.
Around here it's mostly the turnpike, or at least they can afford to spray way more than anyone else.
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