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Frequently Asked Questions About Diesel Exhaust Fluid (DEF)

What Happens If My Vehicle Runs Out of DEF?

Most manufacturers have added instrument gauges and indicators to vehicle dashboards.


When DEF gets low, the indicator will display as a warning to fill up.


If you do not refill and run out of DEF entirely, an emergency light will come on, and the vehicle’s performance will reduce, such as the engine’s speed running at only five mph.

To ensure this doesn’t happen, it’s best to always carry a bottle of DEF with you, so you don’t get stuck.



Is It Safe to Refill DEF Myself?

DEF is non-flammable, non-hazardous, and non-toxic to humans or animals. It is safe to store and handle. So it is safe to refill DEF once it is low.


How Often Do I Need to Refill DEF?

Approximately, you’ll need 2.5 gallons of DEF every 800 miles, which makes diesel consumption about 2 - 3% of diesel consumed. That means you’ll need around 2 to 3 gallons of DEF for every 100 gallons of diesel.


However, that may be different depending on the make and model of your vehicle.


The most important thing is to ensure you don’t run out of DEF by partnering with a reliable bulk supplier that can deliver to your bulk DEF tank or directly into your vehicle at your facility.


Where Can I Buy DEF?

DEF is available in several locations across the country. If you need DEF in Lancaster, PA, you can get a steady supply at our location 24-7.


The good thing is that we can deliver DEF to you no matter where you are. Our custom-fitted delivery fleet can refill your DEF storage tanks at your facility. DEF is also available in smaller sizes, from 2.5 gal jugs to 330 gal. totes.


How Much Does DEF Cost?

DEF prices vary depending on the quality and quantity you need. Contact us today for more information on our pricing options.


I Already Have a Supplier. Can I Switch to Another?

Yes, you can switch to another supplier. If you have DEF left in your tank, let it run low before refilling. You don’t have to clean out your DEF tank unless the DEF is contaminated.


While DEF is DEF anywhere, there will always be companies that cut corners with the manufacturing, which is why you need a trusted supplier like Susquehanna Sales & Services.



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