Garmin Service Alert: Fuel Quantity Indication Error
Garmin has published Service Alert 20137. When operating at low fuel, some Garmin G3X and GI 275 fuel quantity gauges may erroneously indicate up to four gallons when the tank is actually empty.
More information in the Garmin website: https://www.garmin.com/en-US/aviationalerts/service-alert-20137-fuel-quantity-indication-error/
Garmin Safety alert 20137: https://s23634.pcdn.co/en-US/aviationalerts/wp-content/uploads/2020/12/20137A.pdf