Q: What is the best way to clean my fleet with corrosion protection in mind?
A: Every fleet should have a maintenance schedule that includes cleaning inside and out. More than running through a simple car or truck wash, fleets should focus on the five factors important to exterior cleaning of the under chassis and body: water quality, temperature, time, mechanical action and chemical action.
When it comes to water quality, the fewer dissolved solids the better. If you have too much calcium or magnesium in your water, you have hard water. That can reduce the cleaning power right off the bat. Second is temperature where the higher the temperature the better the cleaning power. A good suggestion is to keep the cleaning solution between 100 degrees F and 120 degrees F. In fact, higher temperature water, detergent, vehicle parts, even warmer ambient air temperatures all have higher energy and are better for cleaning. When matter is heated it is in a more excited state; molecular movement is then increased. As a result, this extra movement or vibration aides in cleaning effectiveness.
Time is the next factor to focus on when cleaning during a maintenance schedule. More specifically we would call this ‘dwell time’ or how long the active chemical is in contact with the metal during cleaning (the longer the contact time, the better). Next, we come to mechanical action or the amount of force the detergent mix hits the part. Mechanical action, also called impingement, can be the force applied by a cleaning brush or the water pressure.
Finally and most important, when it comes to cleaning and removing salt and deicers, the proper chemical action needs to be created. Classic detergents can encompass road dirt, oil, and soil, and then need to lift and remove them. One critical point of detergent choice is pH. A low pH (less than 7) detergent can solubilize the salts to remove them while detergents at other pH levels do not accomplish this. Low pH detergents also have the benefit of actually helping prevent corrosion when not fully rinsed off almost leaving a coating behind.
Information provided by: Sherwin-Williams Automotive Finishes
