Road trips put you at the mercy of whatever place is closest when it comes to making a pit stop, and the same goes for when you really gotta pee.

You look around, see the car's gas gauge and think you don't need gas so you'll just pull off the highway and into a fast food restaurant.

Little did you know that some fast food restaurant bathrooms are dirtier than others.

Restaurant Business Online offered up a list of the five cleanest - and dirtiest fast food restaurant bathrooms, saying "fewer than half (47.4%) of customers say the fast-food restaurant’s bathroom they recently frequented was very clean, suggesting that many chains have room to improve."

Here are the five cleanest fast-food restaurant bathrooms:

Culver's and Chick-fil-A tied for having the cleanest bathrooms scoring a 65% cleanliness rating, followed by Potbelly at 58%. All three of those fast-food restaurants are in Rockford and from what I recall, they were pretty clean.

Rounding out the top five is Whataburger at #4 with 57.8% and Caribou Coffee at #5 with 57.7%

The dirtiest fast-food bathroom according to the study was SONIC Drive-In, scoring a measly 30.1%.

Restaurant Business Online says "Three in 10 recent customers rated SONIC Drive-In’s bathroom facilities as very clean, 36.5% below the QSR average for restroom cleanliness."

Other fast-food restaurants on the list include Popeye's Louisiana Kitchen (33.7%), Little Caesar's (33.8%), McDonald's (35.3%) and Jack in the Box (35.6%).

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Sweet Lenny is the brand manager of 97ZOK and Operations Manager for Townsquare Media Rockford. Catch him afternoons 3 to 7 on 97ZOK. Follow him on Twitter, Instagram and like his page on Facebook.

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