If you’re not familiar with the expression, “When you hear hoofbeats think horses, not zebras,” it means that when searching for an explanation, you should always consider obvious possibilities before thinking about more unlikely options.

I recently wrote about monthly club-plan pricing models. And since then, I’ve spoken with several readers experiencing levels of wash club membership churn. You know, the customers that sign-up, often discounted, and then don’t renew. I find that the conversation can go down a path of discussing the improbable rather than trying the simple things first. The simple things that often work! Today, I’m going to cover a common cause for churn and not suspect the rare and unusual. Let’s talk about the fundamentals of delivering a clean, dry, shiny car. Afterall, the odds are your wash can remedy a good portion of membership churn from this common diagnosis.


It’s rare these days to enter a car wash and find a brush spinning the wrong way or to come across a wash with insufficient soap or premium chemistry. These once common mistakes are typically found early and fixed fast. Our industry has come a long way with delivering a shiny car.

But this isn’t always the case with drying. We still see dissatisfied customers with water and foam streaming across their vehicle. This is a drying problem and it’s a good place for us to start.

Drying Is Delicate

Proper drying is a precise recipe. You must be in-the-know and in control of water quality, pH, detergent, equipment, temperature, and more. You never want to assume that what you did at one wash will work at every wash. Adding more of one ingredient won’t normally solve a drying problem. Likewise, removing one ingredient won’t work either. And simply adding more blowers won’t get every drop. Everything has to be “just right.”

Drip Space is Dead

Somewhere buried deep on my desk, I’m sure I have a chart referencing an obsolete requirement for 20 feet of drip space. Over my career, I’ve witnessed the minimum drip-space requirement drop from 20, to 15, and more recently to 10 feet. Lately I’ve watched tunnels push the envelope with as little as 5 feet of drip space.

The combined advancements in water treatment, chemistry, and computer controls have caused the rules to be rewritten — at a cost. Reducing the amount of drip space in your tunnel makes it more difficult to deliver a dry vehicle. That fact cannot be escaped.

Real estate in the tunnel is precious, so it seems to make sense to cut down drip space. You may need the drip space to slot in additional equipment to replace prep labor, or to increase chain speed to process more cars, or to add a friction polishing machine to improve customer satisfaction.

Whatever the reason, you can absolutely cut down on drip space. But only if you invest time and effort to master the water, chemical, and equipment aspects of the drying process. There’s no free lunch.

Drying Begins at the Beginning

Most drying issues — and opportunities to reduce drip space — originate at the beginning of the tunnel.

First, you cannot dry a dirty car. Second, you cannot clean a car without an alkaline presoak and sufficient friction. Third, most city water is alkaline at a pH of 7 or above, which is done intentionally to protect pipes. Fourth, and here’s the kicker, you can’t dry an alkaline car.

You see the conundrum. The process of cleaning raises the alkalinity of the vehicle’s surface. And a vehicle must enter the final rinse with a slightly acidic pH (ideally 4-5) otherwise, it’s difficult to dry the vehicle.

So, how do you go about this? The most obvious is that you need to know what’s in your fresh water supply. Send out a bottle and get it tested. There are many tools available to you — everything from water softeners, spot-free reject water; to conditioning the pH of water before using it to mix with chemistry. Balancing pH through the wash process primes the vehicle for effective drying.

Next, work with your chemical supplier. There’s a reason most have multiple options for each chemical function in the tunnel. Your chemical supplier will help you select the optimal pre-soak, priming, sealing, and wax applications to produce a slightly acidic surface before entering the final rinse.

Rinse the Car Dry

Now that you have a perfectly clean car entering the final rinse at a slightly acidic pH, it’s time to rinse the car dry.

The first rinse curtain should be a conditioned freshwater rinse to remove foam. Followed by a drying agent application to make the surface of the vehicle “hydrophobic,” which literally means afraid of water. Drying agents promote water to pool and break off the vehicle surface. When used properly they will leave residual droplets that your drying system can handle.

Too little drying agent and water won’t break. Too much drying agent and water won’t break — plus you can get spotting. Each manufacturer offers multiple drying agents with recommended concentrations for a reason. Although they all use similar raw materials, variations in temperature, conveyor speed, water quality, and available drip space call for different products.

Some drying agents are promoted as a drying agent and sealer wax in one. The two products are similar. I prefer to use a distinct drying agent followed by a separate sealer wax that also enhances sheen.

Spot Free Considerations

Some operators will argue that spot-free rinse is an unnecessary expense. I consider it a form of insurance that my customer will be satisfied with the finished product for days to come.

Personally, I apply spot-free water to every car. I only promote it, however, in my upper wash packages. Added value to help bump a customer to a higher ticket never hurts after all.

You Can’t Dry a Car with Wet Air

Start by using a rinsing system that doesn’t create mist. For years, zero-degree “rain curtain” manifolds combined with 20 feet of drip space and blower inlets pulling from the tunnel exit delivered dry cars at the highest chain speeds. Occasionally, environmental factors, such as temperature and humidity, demanded building a physical barrier or wall in the tunnel to block mist from dryers.

Having that old-fashioned 20 feet of drip space let tunnel mist settle so blowers didn’t recirculate it. Eliminate the drip space and you may need to erect a physical barrier such as a wall or arch to help cut down on mist being recirculated by the blowers.

Direct Air off the Vehicle

Various blower nozzles and flipping actions are available to direct residual droplets off the car and to the ground without blowing them onto the next car. Equally important, though, is understanding how to adjust blowers to work in conjunction with one another. Sometimes, moving a blower just a few inches can make a dramatic difference on the finished product.

Buffing Modules Don’t Fix Drying Problems

Spinning brushes at the end of the tunnel with gentle drying materials that flatten out residual water droplets are popular with customers and a great way to distinguish your wash in the market. Not only do the spinning brushes enhance the shine, but they also deliver a towel-dry experience without labor. They won’t, however, solve a drying problem. To work properly the car must be clean and dry before being buffed. Then the buffing unit functions as intended, as icing on the cake.


If you are experiencing a high churn with your monthly memberships or high churn in general, start with the most likely diagnosis. Start with the hoofbeats of clean, dry, and shiny. Odds are the ability to impact churn in a positive way is a more common diagnosis than a rare, improbable one. Get clean, dry, and shiny right and chances are that customers become repeat customers — hoofbeats that many successful operators have been hearing for years.

Good luck and good washing.


Joining the company in 2000, Anthony Analetto serves as the president of Sonny’s CarWash Equipment Division. In this role, Anthony leads the innovation of new products to drive client success and oversees all operations, engineering, and supply chain management. Washing cars for over 30 years, Anthony was the director of operations for a 74-location national car wash chain prior to joining the company.