4 Reasons You Should Never Top Off Your Tank

Do you top off your tank? It’s a common practice that many drivers engage in, as it saves them trips to the station. However, is topping off your tank dangerous to your car or you? Does rounding to the next dollar benefit you in any way?

Perhaps you’re a “tank topper” and don’t realize it. Some folks set the gas pump to autofill. When the pump kicks off, the car is full. However, some people don’t trust the pump and feel there’s room for a bit more, so they manually turn the pump back on, trying to squeeze in more gas.

These individuals wait for the pump to kick off again or try to round up to a specific dollar amount. Both practices are tank-topping, and it’s dangerous for many reasons. You might have learned this habit from your parents or relatives you often traveled with when you were younger.

If you saw your mother or father top off the tank, you likely thought this was standard practice for all drivers. Consequently, you may believe that squeezing another $1-$2 into your tank will help you cut down on trips to the station. If you need to refuel often, it’s understandable to want to avoid these costly stops.

Reasons Why Topping Off Your Tank is a Bad Idea

Cars have evolved over the years, and what was safe for the vehicles back in the 1980s is not the same today. The engines are more intricate as a computer is in control, and let’s not forget about the fuel injection system that replaced troublesome carburetors. What worked twenty years ago on those automobiles may not be the best for today’s more sophisticated machines.

The United States Environmental Protection Agency is the best source for information on this matter. Officials state that not only is topping off your tank a waste of time, but it’s dangerous. Here are some reasons you should skip this all-too-common practice at the pump.

1. The Gas Can Spill Everywhere

The gas pump is a sophisticated piece of equipment with sensors telling it when to shut down. These sensors are in place to ensure the pump doesn’t spill over, causing a huge mess. When you override the shutoffs, you’re taking the risk that the gas will spill on you and around the pump.

Trusting the sensors is best, as you can’t see into the tank. Remember, a spill is more than an inconvenience on your hands and clothing, as gas is a highly flammable substance. Spills are quite dangerous. Gas can seep into the ground, pollute your water supply, and harm wildlife.

2. You’re Wasting Your Money

Another thing to consider is that you’re just putting more gas into the station’s hose rather than your tank. Once the pump clicks off, there’s always a bit lingering inside the hose, which is like your garden hose at home.

When you turn it back on, the gas may be drawn into the vapor line, which will be fed right back into the storage tanks at the station. It’s highly possible that much of the gas from your top-off session isn’t going into your tank at all.

3. It May Shut Down the Pump

Did you know the average gas pump costs $16K – $21K to replace? The systems of today are quite a bit more advanced with credit card readers and digital screens. When you top off your tank, you can cause the machine to become inoperable as a safety precaution, or if it overfills, it can cause damage.

Sure, it might not cause you any direct harm, but it could be a very costly mistake for the station owner. Any repairs needed on these machines will shut down the pump and backup lines at the station. Additionally, the station will eat the cost of the damage. What if the pump malfunctions and messes up on the person next in line?

4. Causes Problems in Your Gas Tank

There’s a reason your tank is indicating to the pump to shut off. While your tank may not be filled to the brim, it doesn’t need to be. The gas needs room to expand inside the tank, as it’s a combustible material.

You’re messing with your car’s vapor collection system when you spend your time and money topping off the tank. All that extra you put in there may evaporate away anyway, and there’s a chance it can mess with your fuel efficiency.

Final Thoughts on Tank Topping

It’s not worth the risk of personal injury, vehicle damage, and environmental harm just to squeeze more into the tank. While it may not cause any damage you can see, your luck may run out. It’s always best to trust the sensors, and replace the nozzle once the pump kicks off.