I wash mine by hand, in my garage. I do it whenever necessary, and sometimes even when not necessary.
I heat my garage with a portable heater, and I have a garden hose split off from the service drop for the water supply to the laundry.
I have it hooked up to the 'HOT' water side only, so it's doubly good in getting all that nasty crap off from the car, especially the under carriage.
Have done this same procedure for all of my cars over the years, and it hasn't failed me yet.
Eats up more time in maintenance each week, but wth, worth it to me.
That is until I can afford to have a junk / beater type car of my own.
But my oldest got her license this year, middle one will be getting hers (well at least her permit) next year.....
So I am kind of obligated to purchase a used car for them, rather than me first..... oh boy, I could see the Wife's comments now if I came home with a beater for me, prior to purchasing a car for the kids.
Yikes!

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