I like this U wash by my work, I took the Tahoe their the other day, $2.00 in quarters gets 5min of hot power washed water.

The truck is waxed up well and it came out great! I plan to do this all winter to that and the camaro frequently.

I kept back a few feet and always waved the wand back and forth, but will the power washed water take off the wax?

 

Any time you wash, you are abrading some of the wax, but as long as you're keeping a good distance, the power wash shouldn't accelerate that too much.