Salt and Snow Can Be Harmful to a Classic, but Your Garage Might Be, Too

Magnifico

Storing an old car during winter is a practice so common that we tend to overlook how damaging it can be. All manner of bad things can and do happen when you take a machine, like a classic car, that’s designed to move and park it. The danger is that three months sometimes turns into six, and trust me, a car’s condition never improves while sitting.  

Really, the best situation is where the car is driven every few weeks when the roads are clear, as this keeps things exercised. If you must park your classic, don’t ignore it. Instead, consider the following before, during, and after hibernation.

Space: The tighter and drier, the better. A fabric shelter is better than nothing, but avoid leaving a car sitting over dirt or grass, as they’re sources of humidity that will accelerate rust.

Rob Siegel storage problems at warehouse cars
Rob Siegel

Car Cover: Yes, even in the garage. It keeps particulate matter, the errant falling rake, and stray rodents off the paint. (FYI, HDC members get 10 percent off on California Car Covers.)

1969 Lotus Elan +2 mouse nuts
Rob Siegel

Speaking of Rodents: They can ruin a car by chewing through fabric and wires, nesting under the hood, or leaving, ahem, presents all over your interior. I throw a Bounce dryer sheet on the floor, in the trunk, and under the hood. The theory is that the critters dislike strong smells. Some people use mothballs or peppermint oil. Anything is better than nothing.

Battery Tender on Honda Goldwing battery
Kyle Smith

Battery: If you have electricity, consider a trickle charger. But be safe about it: Tightly coiled extension cords, fraying wires, and the presence of combustible materials (everything from gasoline tanks to oily rags) can all increase the risk of fire. You might also consider taking the battery out and bringing it to where you can trickle-charge it safely. At minimum, disconnect the negative battery terminal. A healthy battery will probably fire the car right up when connected three months later. Longer than that, you’re pushing it.

Fuel pump install tank interior
Rob Siegel

Fuel: Ethanol attracts water, and when the fuel can no longer absorb it, the ethanol-water mixture sinks to the bottom. The corrosive mix can rust a metal tank. Ethanol-free gasoline is thus best for storage if you can avoid it, but in many areas, that’s becoming difficult. (Pure-gas.org lists stations that sell ethanol-free gas.) If all that’s available is E10 (10 percent ethanol), by all means fill the tank with it, as the less air there is above the fuel, the less opportunity there is for water absorption. There’s little harm in using short-term fuel stabilizers like Sta-Bil and Star Tron. If the car may sit for years, consider using Sunoco Optima race fuel (beware, it’s pricey).

flat tire on austin healey
Kyle Smith

Tires: Sitting eventually causes tires to flat-spot. I pump mine up to 40 psi prior to storage, but the best prevention is minimizing the time the car sits. If you can occasionally roll it a few feet, do so. There are various pads on the market (Tire Cradles, Flatstoppers) that certainly help. But if the tires are precious and you want to eliminate flat-spotting altogether, buy a set of junk wheels and tires for storage.

Rob Siegel - Which winter project is space worthy - IMG_1586_enhance
Rob Siegel

Beware the Winter Project: A big repair seems like an ideal use of the winter downtime—and a way to bond with your car even when it’s not moving. It’s a nice theory that, in my experience, has rarely panned out. My garage has heat and a dedicated “project” space, and I’ve done over-winter A/C retrofits and transmission swaps in it, but the heat in the garage is rarely living-room heat, and I can attest to the daily grind getting to be a bit much. Just remember that working on your classic is supposed to be enjoyable. Maybe say yes to stop-when-you-want tinkering, but leave the engine swap for spring.

Siegel - Spring Rollout - Antifreeze Leak
Rob Siegel

In the Spring: Generally speaking, the longer the car has been in storage, the more careful you should be. At a minimum, check the fluid levels and look under the car for puddles. I’ll often pull the air cleaner housing off just to be certain that a mouse nest isn’t about to get sucked into the engine. Carbureted cars with mechanical fuel pumps typically need help starting. I’ve never seen the harm of a blast or two of starting fluid to get the car running and fuel drawn into the float bowls. My routine is to let the car idle for a minute, shut it off and check for leaks, inflate the tires to spec, then drive it around the block and check again for leaks.

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This story first appeared in the January/February 2025 issue of Hagerty Drivers Club magazine. Join the club to receive our award-winning magazine and enjoy insider access to automotive events, discounts, roadside assistance, and more.

Rob’s latest book, The Best Of The Hack Mechanic™: 35 years of hacks, kluges, and assorted automotive mayhem, is available on Amazon here. His other seven books are available here on Amazon, or you can order personally inscribed copies from Rob’s website, www.robsiegel.com.

Read next Up next: C8 Chevy Corvette Joins the Lego Technic Catalog

Comments

    All excellent advice.

    I especially agree with the winter wrenching. Unless that major part is preventing it being driven when the weather turns, I just like to accumulate a list of smaller, independent fixes that I can chip away at.

    I have several projects that’ll take an hour or two, and a few that require probably a dedicated weekend. But I can tackle them all as separate adventures. None of them stop me from driving the car (unless I stop a job part way through).

    Last year was a full dash replacement, coupled with a “while you’re there” refurb of the HVAC and factory stereo system.
    This was not a small project and I spent most of the winter dreading the project. Only a final push for a big event was enough to motivate re-assembly after all the work was done.
    I’d like to avoid that level of winter commitment.

    This year is things like engine dampers, window sliders, and some re-bushing of the rear suspension. MUCH more bite sized.

    If you have heat winter is the BEST time to tackle a large project. Plenty of time to work on it at your own pace. What else are you going to do when its cold & snowy outside. If you’re not finished by April it’s time to pick up the pace!

    Here is the key to a good garage climate. Heat for sure. But make sure to insulate. Also make sure it is vented properly for air flow.

    Finally there are de humidifiers like Humidex that will control moisture in the garage. This makes it a safe dry environment even if I am washing cars it dries fast.

    These were made to de humidify Canadian garages with heated floors but they work great here if you just want to keep humidity controlled in your garage. No rust on cars and tools.

    I work all winter large and small projects with 70 degrees and in shorts like summer. This little unit really makes a difference.

    But I do a number of jobs large and small to make sure Im ready in the spring and not working to the last min before a show or event.

    I have my garage heated in the winter and humidity controlled in the summer. Definitely makes a big difference, my car never gets any musty smells.

    Spring is the most noticeable. When it is warming up and the garage is cold with high humidity engines and tools can sweat here in the mid west. I no longer have this issue.

    I just keep mine set around 5 degrees (41 for the yanks) during the winter months. It’s electric heat so it doesn’t induce moisture up here.

    Gas heat does not create moisture. it is the humid air from water use or if you pull in a car with snow on it.

    But also humid air if you live in a humid region too. temperature changes can induce moisture build up on a contents of any garage heat can and will duce it but a humidifier will help reduce it more.

    True climate control is heat and humidity.

    Ventilation and air flow in the garage or any building is important too.

    Much depends on where you live. San Diego humidity is seldom an issue. Chicago in winter it is always an issue.

    I also pumped up the tires to 40 PSI and never had any flat spot issues. I usually did small projects and made sure not to do anything with materials that might become brittle in the cold like plastics without being very careful.

    Sound advice on both points. Regarding things breaking in cold weather, it’s challenging enough to be a mechanic AND a finger-style guitarist in warm weather. In cold weather, even with gloves on in the garage, those nails break almost instantly.

    I think the most important of the suggestions is to exercise the car whenever possible. I get it that in the colder climes, there is often little – or no – chance to do it regularly throughout the winter, but unless you live up around the Arctic Circle, there are usually at least a few days where a drive is possible. I’m pretty lucky where I live in that there are a lot of days – although plenty cold – where a spin on a clear, sunny day is possible at least every couple of weeks. The cover comes off, the garage door goes up, and the Pontiac gets to circulate its juices a bit while bringing the grin back to MY face…

    Mine doesn’t leave the driveway until the salt is gone. Plenty of clear days, but the salt is always lurking.

    I’ll only take it out if there’s been a couple of good rain days to wash the salt off the roads. Last couple of years i could get it out every month or so. This year I had one chance about 2 weeks ago and didn’t take it.

    I would love to get the cars out in the winter on decent days, but refuse to do so until all the salt has been washed off the roads. That pretty much never happens until actual spring in these parts.

    I dunno about the dryer sheets trick. After ridding my old 911 of mice in the frunk, I added some dryer sheets, confident this would do the trick. The mice returned, and by the time I discovered them, they had made a virtual condo using the dryer sheets.
    As a fellow guitarist of the same age as Rob, I have significantly less enthusiasm for winter projects than I once did, for the same reasons. Gone are the days of swapping out Fiat transmissions while lying in the snow. My personal chassis is paying for those days now.

    Your “swapping out Fiat transmissions while lying in the snow” comment brought back a memory of swapping the starter on my ’69 Mustang Mach One while laying in the snow in front of my house in upstate NY many years ago. First step: jack the car up and jam a ramp under the front tire, then scoop out most of the snow and roll under the car, then discover the header wouldn’t let the starter come out. Off with the header. Then to the salvage yard for a “good” starter (I was in high school). More snow, more shoveling, more jacking. Bring the good starter back to my house and reverse assemble the Mustang. I wouldn’t even consider that level of effort 45 years later, but loved every minute of it when I was 18.

    For dealing with mice and pest. Traps and poisons are the most effective. I recommend traps as you can contain the body and not have it die in the AC vent.

    Or get a cat. I encourage my neighbors cats to hang around They clean up the pest and I don’t have to care for them. We also have a number of Ferrell cat that get cycled out by the Coyotes.

    It is all the circle of life.

    I always leave the hood up in garage when covered. Those pesky rodents love warm, quiet, dark places to hide. Also, I cover tailpipe (not when just run) and pump tires up to max psi if I am not going to drive for a month or so. Some essential oils on a rag in an open plastic bag help on rodents as well and interior and trunk will smell better when driving season returns.

    I have a small well insulated shop with a big heater, and still find it hard to get out there anymore. The 67 stays in the front garage, and as long as the roads are dry, the salt isn’t much of a bother. It lifts the spirits to go for a rip in the gray days. Hopefully enough will melt off that I can get it out out in a week or so. -7 this morning, ugh.

    If you own a cat or encourage cats to help with rodent control, PLEASE,PLEASE don’t use any poison or traps!! We love our cars, but most of us love our pets more. The death of a cat that’s been poisoned is quite horrific.
    Thank you!

    From what I’ve read, the problem with mice is that they adapt. Eucalyptus oil works well – for a month or two. Irish Spring works for a few weeks. Some of the electronic units work in labs and not in garages. Dryer sheets work for about a week. So, try any strong smell (like Citronella oil) for a few weeks and change to another.

    An Irish Spring anecdote: We had wood rats visiting our backyard vegetable and flower gardens a few years back in southern Ontario and my wife read about Irish Spring so she sacrificed a few bars into small pieces. One evening we were eating dinner on the back deck and watched a rat pick up the pieces one-by-one and take them off to his burrow. I rationalized that at least we had the cleanest rats in the neighborhood!

    A bit of a twist on the “winter” storage.
    Please help with “summer” storage. Coastal Mexico…and I assume Florida….continues with the critter problem but humidity is an issue. I use dryer sheets, desiccant ( 2 tups last year…4 for this year) and have a cover. Thank you Hagarty for the CaliCover discount.
    With the cover and top of the window vents should I have all 4 window down an inch ? or just close it up.
    Any help greatly appreciated….

    Until last Spring, gasoline without alcohol was unavailable here in New Jersey. Then it became available in small quantities for use in lawn mowers and such. It’s available at Lowes and Home Depot in 2.2 gallon cans for a bit over $40. That’s much higher than aviation fuel!

    There are a few marinas around that sell gasoline without alcohol, but none near me. I expect the prices are pretty high, since that would have to be trucked in.

    Years ago I moved from CO, dry country, to WI, my ’56 Chevy Nomad went in the moving van with my furniture. We bought an older house on arrival in WI, it had a newer oversize 2 1/2 car detached garage, hey great. So come the 1st Spring, I noticed some moisture on the garage floor, not concerning. Later in Spring I looked under the car & the whole undercarriage had surface rust. The Nomad was an original CO car, totally rust free. Come to figure, when they poured the slabe, they hadn’t put a moisture barrier down 1st. If I would have known, I would have bagged the car. No heat in the garage for warm/cool effect, didn’t matter, frost coming out of the ground in the Spring, beware to the unknowing.

    I’ve learned this the hard way as well. This season I have a tarp down to hopefully capture any moisture between the concrete floor and the car.
    Great article and suggestions, come on spring!

    Rapid change in temperature creates tons of moisture. I finally learned to keep my garage doors closed all the time in summer and winter. I used to open up the doors on a warm day to “air out” the garage and it would turn into a terrarium. You could watch the sweat form on the floor as the warm air hit it. I also put a dehumidifier in my garage that works great. The concrete floor act as a heat sync and the garage stays cool and dry all summer if the doors stay closed. It can be 90 degrees for several days in a row and the garage never goes above 70 degrees.

    Aviation fuel contains lead, a LOT of lead, so if you use it for winter storage, drain it and flush it several times with auto gas. Lead destroys catalytic converters. If your car is pre-cat, avgas is fine (if not legal for road use), and about twice the price of auto gas. Lead-free racing fuel is a better, if more expensive, choice for cat-equipped cars.

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