September is the last good month of the year for a lot of us. October comes and it is raining every other day and the temperature just fluctuates too much. In my case I usually get snow by the end of the month and November is just as bad. September is when I start the Winter Detailing prep work for my vehicles. In fact, from September through May I am closed for any and all new business for detailing. Only my loyal regulars get work done since the work usually takes longer and I can't stack as many cars in one day as when it is just a summer maintenance type deal. Winter detail prep is something that is best done in September when the weather is still nice and winter is just right around the corner.
Here are a few things to consider for your winterization of your daily driver this season.
-Wheels: I like to take the wheels off and put a coat of sealant on them. It gives me a chance to scrub them good and hard and get them really clean before they are pounded by months of neglect while being covered in salt. My sealant of choice is Klasse simply because of how durable it is. You can use any sealant you have handy. Just avoid the waxes. They just don't last very long. Chances are it won't last through September if you did it now, so skip the wax and go for a sealant.
-Paint: The Fall Detail means clay bar, polish, and sealant. Get the tree sap off and get rid of the swirls by claying and polishing the paint. Then get a good sealant on there to protect it from the salt and grossness of what is going to be slung up by your tires over the next few months. If you are using Klasse then I recommend at least 3 coats over a period of a few days for maximum shine and protection. In fact, with any sealant I would absolutely recommend more than one coat. Unlike a wax, which just blends layers together when you apply them, sealants cure on the surface and can be layered. Most sealants require 24 hours of cure time between coats, but some include a cure accelerator in them which eliminates the cure time. Wolfgang and 4*Ultimate are a couple of those sealants. I'm not sure about the new Meguiar's Ultimate Liquid Wax. I'd give it a day between coats just to be on the safe side.
Windows: Don't use paint products on your windows. There are products like RainX and Aquapel out there for a reason. Coat your glass with them to create a surface where water beads up and zips off from when you are driving. A fresh coat of RainX will even cause your windows to freeze at lower temperatures. I did a test once to try and demo an ice scraper and I couldn't get my windows to freeze overnight to save my life. I don't know if it was just super dry or what, but it wouldn't work. I had to spray water on the glass with a spray bottle and try to demonstrate it that way, but it just froze into little beads of ice. Glass treatments are awesome in the winter.
Exterior trim: Wolfgang has a new trim sealant that I'm dying to try out this winter. Right now there isn't anything i've found to avoid the salt stains and just generally nasty look that areas like the wiper cowl and step guards on vehicles get during the winter. I'll be hopefully picking a bottle of this up soon and will let you know. For now I can just suggest you keep them protected with a good product like Aerospace 303.
Tires: Yeah, not much you can do there either. Just keep em clean when you can and shine them up if you get a chance and there is a break in the weather. I typically don't do much for my tires during the winter because nothing really helps which is out there right now.
Carpets: They get nasty with salt in the winter and I don't know what to tell you. Get winter mats if you can, but otherwise just keep your mats clean by vacuuming them when you get a chance and kicking the snow off your feet before getting in. Your washing machine is your friend. Throw your mats in there every couple months and they'll stay looking a lot cleaner. I know someone who puts packing tape around the edges of his mats in the winter since those areas are the hardest to clean. Not a bad idea... Not pretty, but better than having salt encrusted borders on your floor mats.
Leather: Winter doesn't really affect leather, but it does affect leather conditioner. When the leather is frozen you can't get the conditioner to soak in. It is best to condition your leather when the conditioner is warmed up and your car is warmed up. Don't try doing that in temperatures below 40 or you'll just waste product and make a mess.
There are a few products you may want to bring in from the garage during the winter. Your sealants will probably be fine, and your waxes will be even better. Since tire shine doesn't work when it is cold, you might want to bring that in though. In fact, anything meant to clean anything should be brought indoors. Freezing does something funny to cleaners. Other than that, you shouldn't have to worry much.
Oh, don't forget to polish your exhaust tips. It likely won't get done for the next four or five months, so you might as well start out with a clean one. A little chrome polish, or even paint polish, and a rag will do wonders. You can use paint sealant on them afterwards, but the heat will probably vaporize it after not long. Your best bet is just to stay on top of it. A little glass cleaner and a towel will do the trick if you stay on top of it.
Hopefully this has been of some use. I know not everybody is as nutty as I am about car care, but my cars are among the top five most expensive things I've ever bought in my life, so they sort of fit high on the priority list of taking care of them.
Unless your car was given to you, then you are probably in the same boat. I don't know many things other than your house and your education that you are going to drop twenty or thirty thousand dollars on and use every single day. I will say that your vehicle represents an investment of money, and if you want to see as much of that investment come back to you someday when you sell it, then caring for it in this way is a great idea.