Most of the automatics have a height, length, and width restriction. I don't fit in the local brushless with my extended height topper and stacks will probably cause the same problems. I took it off this winter and will try it some time. Not sure if the length is a problem, but it will be close.
Another local Rammer found out his dually doesn't fit in all automatics, too.
I spent part of my afternoon at the local self wash. It wasn't busy so I took my sweet time. I bring 5 gallons of warm water, a bucket, and my car wash soap. I power wash the top and bottom sides then hand wash the entire top side. I finish off with 2 rinse cycles. When I take my time, all the collected ice, sand, salt on the bottom side drops so I can give it a good rinse.
A dry towel to wipe all the weather stripping to prevent freezing and I'm on my way.
If you can find an automatic to fit the Ram, here is another option:
Go to the self wash and rinse the entire bottom side. Use 2 cycles and get all the frozen crap knocked loose.
Drive to the automatic and get the top side clean and take yout time through the air curtain dryer. I always carry a rag and dry the weather stripping to prevent freezing.
Sorry for the long post, but when you live in the land of ice, snow, sand & <em>salt</em> one can never be too AR...
-john