Each Spring and fall I take about an 800 mile "hike" from either Michigan or South Carolina to the other one.,.... I wash and wax just before leaving.
Wash: I usually use Spic & Span on the roof, And "Car wash concentrate" on the sides, both diluted with water (on the sides I use a car wash "Gun" that does the dilution automatically)
On both I use a long handled "Van wash" brush This telescoping handle brush has "Flow through" but I do not use that.
Wax, (NOT ON THE ROOF) is any good cream, liquid or Foam wax. Meguilers (I can not spell that name worth ... deleted...) is a good brand but Turtle Wax works nearly as well.
Suggestion.. Before you wash and wax take a trip note MPG
After: Same trip, and note.
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