Mythbusting: Seasonal Storage


As Thanksgiving nears, it’s time for those of us in cold weather areas to put our precious rides away before the white stuff (snow) falls and more white stuff (salt) is spread onto roads in quantities sufficient to cause bridge decks to collapse.

This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2017/11/17/mythbusting-seasonal-storage


Well done article, dispelling myths, and your insight, “leery of any claim from any additive manufacturer that a gas stabilizer can remove water that has already separated”. Most experienced mechanics treat the ‘additive market’ with disdain, a waste of cash, as any measurement of ++ results is largely subjective.

Although I’ve always had available, but rarely used, Marvel Mystery, Techron, Seafoam…etc., I had read favorable reviews on BG44K.

(Full disclosure : I have no currency involved, no ownership position, no friend at the factory, and I’m willing to be polygraphed, mirandized, breathalyzed, and submit a urine sample, if subjected to a deposition.)

My strategy for the last five winters (seven vehicles) is top the tank with 93º EtOH free petrol (the only fuel we use year-round). We’re fortunate to live < 3 miles from a BP station that provides ‘recreational’ gas. Then add the prescribed amount of BG44k + Sta-Bil, i.e., the marine grade that is blue, not the red, and then drive the vehicle a minimum of 30 miles at speed. The sta-bil, ostensibly, has the highest hygroscopic capability. The BG44K is not cheap…a case of 12, 11oz per can) runs ~ $200.

The target dates for storage, weather permitting, is to go to bed on Halloween, and wake up on April Fool’s, ~ five months.

Does it work ? Well, every car (age range 1958-1983) has started almost effortlessly. That has become the litmus test. Now, do I get better mileage, higher performance, consistent idle…?..I can’t really address any unmeasurable parameter. Nor am I able to wipe the smile off my face when back on the road. Kind regards, Dr. C.


Any thoughts on changing the oil and filter before storage? I usually do this, but with synthetic oils, is this a waste of time?

I also have my Lotus up on structural foam Race Ramps, which may reduce flat spotting on tires - YRMV.

Love the articles, Rob!


What I do for winter storage:
Wash maybe wax the car
Grease, inspect, change oil and filter from a warmed up engine
Overinflate the tires 10lbs
Fill gas tank and use stabilizer
Put Irish spring soap shavings and bounce dryer sheets every where including trunk and engine(remember engine in spring)
Disconnect battery and use a battery maintenance charger
Drive onto tire “pads” of some kind
Cover the car

I also use the right amount of Camguard in the oil to protect the engine from rust (look up Camguard—it’s good stuff).
Larry Pack MD


I use Shell V-power year-round, which comes with an ethanol-free label on the pump. My three English cars get 40 lbs. in the tires, a filter and hi-mileage 10W30 in the fall (contains seal conditioners), and a drain and synthetic 5W50 fill in the spring. Fuel stabilizer (not really measured). The battery comes to a warm room where there’s no electricity, and chargers for the others. Covers, of course.(We don’t have walls all the way round, and sand can blow in with the snow)


A good friend of mine and ex-Ferrari race mechanic (did Le Mans 3 times) recommends adding half a cup of Automatic Transmission Fluid to the fuel tank before topping up and then running the engine for 10 minutes. This applies ONLY to carburator cars. The oil coats the fuel tank, lines and carb bowls and helps avoid corrosion. It will easily burn off when you restart the car.


Another very helpful article. Thanks very much Rob.


Another thing I always do is put about 50LBs in the tires and then park on 12" squares of plywood under the tires. Never had a flat spot, but if you forget to deflate the tires to normal, the first ride will be rather bumpy.


I would like to reply about the battery and concrete floor thing. This mainly refers to old unheated and uninsulated garages. If the outside temp drops way Low, The concrete near a wall or doorway may act as a heat sink and draw Temp out of the battery. This can cause the acid water solution, in a low charge battery, to freeze, thus warping the plates and shorting them out. Thus the idea of setting a battery on a board and having the board act as an insulator. Granted, newer batteries have individually enveloped plates and therefore do not short. But in old batteries, this was a main cause of battery failure. This idea of concrete storage of batteries started way back in the twenties and thirties, so you can understand the problems experienced at that time. Small note, industrial grade batteries have the bottom end of the plates embedded in plastic case bottoms so as to prevent plate breakage and warping due to vibration.


I’m sure if you talk to each classic car owner you will get a different opinion on how to store a classic car, but since this method works for me I thought I would share it.

First of all, I’m the type of guy that likes to do everything now, so that when spring rolls around I can simply get in the car and begin enjoying it for another season. I start by changing the oil and filter. Old oil contains contaminants, especially if you use the car infrequently and on short trips. I perform any routine maintenance that is due, and I don’t forget to service the air and fuel filters. I check to make sure I have a 50/50 mix of antifreeze and water in the cooling system, which will show -34 degrees Fahrenheit on an antifreeze tester.

Your cars biggest villain is rust, that’s why I clean the car inside and out, and wax it prior to putting it in storage. For extra protection, I generously wax the bumpers and other chrome surfaces, but I do not buff out the wax. Mildew can form on the interior; to prevent this I treat the vinyl, plastic and rubber surfaces with a product such as Armor All.

Ideally, you car should be stored in a clean, dry garage. I prepare the floor of the storage area by laying down a layer of plastic drop cloth, followed by cardboard. The plastic drop cloth and cardboard act as a barrier to keep the moisture that is in the ground from seeping through the cement floor and attacking the underside of my car.

Now it’s time to prepare the car for hibernation. I drive the car to the gas station and add fuel stabilizer in the amount recommended on the bottle. Then I fill the fuel tank to the top to prevent condensation from forming in the fuel tank while the car is sitting in storage. By adding the fuel after the stabilizer, it will mix thoroughly in the fuel tank. I am fortunate that there is a gas station near where I live that sells 100% gasoline.

Now comes my favorite part, I take the car for a long drive! By doing this l accomplish several things. First, you will circulate fresh oil through the engine, much of which will remain there to prevent rust until spring. Second, you will burn off many of the contaminants in the oil, one of which is water. Third, you will get the exhaust system hot enough to burn off any moisture, thus preventing, or minimizing, rust in the exhaust system. Most exhaust systems rust from the inside out, not the outside in. Fourth, a trip that is long enough to get the car up to operating temperature is also long enough for the fuel you treated with fuel stabilizer to reach the carburetor and all of its small passages.

I inflate the tires to 5 Psi over the maximum pressure indicated on the sidewalls. Keep in mind the tires are warm, and the inflation pressure will drop when they cool off. When I park the car in the storage area, I park it so the tires sit on top of carpet squares. I never put the car up on blocks. Suspensions were not designed to hang in mid-air for months at a time. The tires were designed to sit on the ground for their entire life, and by over inflating the tires flat-spots should not be an issue.

To deter rodents from entering my classic car while it is in storage, I have found that one of the best things to use is multiple sheets of a fabric softener inside the car. There is very low odor associated with the fabric softener sheets after taking the car out of storage, yet rodents hate the smell of them.

The final step is to fog out the engine. I do this once the car is parked where it is to be stored for the winter, and while it is still warm from its trip. Remove the air cleaner and spray engine fogging oil into the carburetor with the engine running at a high idle. Once I see smoke coming out of the exhaust, I shut off the engine and replace the air cleaner. Fogging out the engine coats many of the internal engine surfaces, as well as the inside of the exhaust with a coating of oil designed to prevent rust formation.

I do not start the engine periodically, because I feel that it does more harm than good. Most engine wear takes place when an engine is started cold. This is made even worse when an engine that has been sitting for an extended period of time is started, because much of the protective coating of oil on vital surfaces will be minimized or removed all together.

Finally, I disconnect the battery and put it on a maintainer and let my car hibernate for the winter months.


Great article on long term and winter storage. There was no mention about what, if anything, needs to be done with engine oil, filters, tranny and diff fluids… How about radiator fluid? Being a bit anal like I am, I drain ALL fluids for long term storage. Gas, oil, gear lube, radiator fluid and sometimes even brake fluid. An ounce or two of Marvel Mystery oil or regular engine oil in each cylinder after draining the crankcase coats cylinder walls and rings.
Appreciate any thoughts. Thanks, Jerry


A lot of good comments here, most of which I agree with. I also recommend using plastic sheeting underneath the car to act as a vapor barrier. This is especially true whe parked in a garage that may be wet and salty during the winter if your daily driver is parked next to it.


Not for nothing but this is my experience in storing my 64 for the last 21 years of owning it. Granted the first 7 years she lived in her barn find state; then I got it going and stored it annually. It’s a baseball car. Out on opening day and put to sleep during the World Series.

I have stored in my garage(no heat concrete floor) no issues in the last 7 years. Fill the gas add Sea Foam, disconnect negative cable (as I do even for more than a few days.) She fires right up and drives smooth every time. NO COVER

The only time I covered was years ago when stored in the shop side of my machine shed. No heat that year and the condensation from the concrete caused rust on my bumpers where the cover was tight. The next year I had it in the dirt floor shed and the mice used the cover ties as rope latters to get in.

That brings me to heated storage. If you don’t have rodent protection for the building the mice like to stay warm. They will cover your heated storage just like you do. If you store at outside temps the mice have little reason to seek refuge with your car. If you really need ultimate protection from mice put the car on jack stands with wheels removed and stands in cut off buckets filled with oil or antifreeze. The sorry 4 legged beasts will meet there timely demise at the bottom of the bucket if they make it that far but at least not in your car!

Now on to fuel. I was in parts sales for 15 years. I sold all the snake oil you have ever seen. I worked with many reps who all had the “best thing” for you. Mostly all LIES! I will attest to one thing we did as a test. The red Stabil works by creating a film coat over the gas to seal out oxygen and condensation (it was a different companies rep that showed me this technology) and that dose work. Our test was with small engine push mowers in a city shop. 1/3 were treated with Sta-Bil the others with Seafoam rest were control. All lined up 12 in a row. In the spring 2 of 4 Sta-Bil started all Seafoam started and 1 untreated fired. The 2 Sta-Bil that did not start had been moved around to get to other things in the winter. That was confirmation to me the technology worked, unfortunately if you upset that thin layer it loses your protection.

Long story longer use Sta-Bil if you want but don’t move it run it or disturb it after you poor it in. Read the label. I personally use Seafoam (have since it was $2.50 a can;wish it still was.)

Just the observations of a Snake oil salesman and long time classic car owner.


Doug7740 has it right! That is the most fully in-depth storage methods available. Hey Doug, if you ever find yourself selling a classic you stored for 20+ years call me first. A fresh battery and that thing will run off the key!
Great comment and attention to detail your car(s) are lucky to have you!


I have removed mice nests from the intersection of the starter and the ring gear, the glovebox and from the back of the seat back in my '49 Chevy pickup.
Those experiences make me cautious about using a car cover in my unheated garage. I don’t want them to have privacy when they are house hunting.


I would have liked to read about your thoughts or experiences with the solar battery maintainers.

Something I also noticed is that you did not mention changing your oil before storage. I have often been told of the pearls of storing a car with oil that is close to its change mileage because the sulfur in the oil can combine with moisture in the engine to form sulfuric acid. I feel this is bunk, but I like the idea of my car being ready for driving season the day I take it out, well that and I also like to take the car out a few times over the winter, top down, weather permitting.


Very good information Rob and everyone else. As a self storage facility and warehouse owner. Where I have been storing clients and my own cars for many years. The dryer sheet thing still amazes me. It really does work


Enjoyed everyone’s feedback pertaining to the protective steps taken by passionate classic car owners. After blue printing, balancing and re-sleeving all 8 cylinders on my 396 I decided to run with Evans waterless coolant as well, so hopefully the block, rad and heater core are one less worry. I’ve always felt that the cooling system is near the top on the ‘neglected list’. Picked up some good tips reading everyone’s take on long term storage. Thanks!!


Lots of good information. If only the weather here in the northeast allowed us to drive our nice cars all year. But it’s like a novelty to get my car out of storage every spring.
I’ve been storing my car in a “car jacket” for many years. It’s like a huge plastic sleeping bag. I put the car in the bag on those rubber type “tire cradles” with cookie baking sheets full of desicant to absorb any local moisture and zip it closed.
My car comes out exactly the way it went in. No rotor surface rust, no dust and no rodent problems.


@Ken - I agree with you that the cooling system often is considered “set it and forget it” and unless there is a problem not many people look at it. I’ll admit I’m happy to play with air cooled classics simply to remove that freezing fear!