I had a conversation today with the Parts Manager for an Audi store near me. He told me the following:

1.) They add 2.5 gallons of AdBlue/DEF at the Pre Delivery Inspection, aka PDI.

2.) They add 5 gallons at the 5,000 Service.

3.) As long as additions of AdBlue/DEF are made before the low AdBlue warning is illuminated in the instrument cluster, you can add as much AdBlue/DEF as the tank will allow; and it is not necessary to do an adaptation on the level sensor. If the low level warning is triggered, you will have to do an adaptation.

In other words, if you keep topping it off before the warning, you'll never have to do an adaptation.

I had somewhat surmised that from reading between the lines in the Audi literature, but was not sure until told this today.

YMMV. Time will tell.

I had a conversation today with the Parts Manager for an Audi store near me. He told me the following:

3.) As long as additions of AdBlue/DEF are made before the low AdBlue warning is illuminated in the instrument cluster, you can add as much AdBlue/DEF as the tank will allow; and it is not necessary to do an adaptation on the level sensor.

Hi,I'm a newbie to AudiWorld but not to diesels.I'm wondering if it's ever been pointed out that "AdBlue" has a shelf life (both in the bottle and in the vehicle) and can "go bad"? BMW requires (and automatically does under "free" maintenence) that the AdBlue tanks be emptied,"flushed",and refilled at least every year,regardless of mileage,most likely so that no old DEF is allowed to remain in the tank.Is Audi's official position different? Just curious.

Hi,I'm a newbie to AudiWorld but not to diesels.I'm wondering if it's ever been pointed out that "AdBlue" has a shelf life (both in the bottle and in the vehicle) and can "go bad"? BMW requires (and automatically does under "free" maintenence) that the AdBlue tanks be emptied,"flushed",and refilled at least every year,regardless of mileage,most likely so that no old DEF is allowed to remain in the tank.Is Audi's official position different? Just curious.

Parts Manager told me that the Diesel Exhaust Fluid aka DEF, AdBlue and/or Urea has a shelf life of one year.

The service procedures do not mention draining the old fluid, but do say to completely fill (23 liters) with fresh fluid. 23 liters is the size of the AdBlue tank; so that does seem to indicate that it should be drained first..