1300 Miles And DEF Gauge Still At Full...
 

Maybe the dealer got it REALLY full? My DEF gauge is very good at showing a drain on the DEF when I'm towing.

towing vs non towing effects the consumption rate.

DEF is used to reduce the NOx of high combustion temps. If you are idling around a lot, Your combustion temps may not get very high and hence you may not use much DEF.

Don't worry about. 5000-6000-7000 miles you will need to add some. Your '18 model has the larger tank I think at over 7 gallons. So you will have to fill less often than the guys with the '11-16 trucks

Don't worry about it. Particularly if it was really full. It's really a non-event. Just check it/refill on the 5000 mile marks (5/10/15/20k, etc). Otherwise, forget about it and enjoy the drive.

You must not tow much....I get 300-400 miles a gallon. I have to fill up the 7 gallon tank (2017) every 2-3000 miles.

To the OP: Its basically directly proportional to the fuel economy of the truck. Do a lot of highway cruising and getting 18mpg? your not going to use much DEF. Towing heavy and getting 7-9MPG? That's a whole different story. Either way - don't worry about it until the Truck tells you - it will give you plenty of warning.

My low mileage 39,000 miles, 2015 6.7L goes 225 miles and does a regen for 20 miles. Isn't that too often? Is it because I don't do a lot of long stretch highway miles but only local driving?

You need to read your owner's manual, Ken. If you don't have the paper version, you can download it from Ford. For example, from my 2018 manual: "The
frequency and duration of regeneration fluctuates by how you drive your vehicle, outside air temperature and altitude. For most driving, regeneration frequency varies from 100–500 mi (160–805 km) between occurrences and each occurrence lasts 9–35 minutes."

If all you do is city driving and short trips then this is normal. You need to get this truck out and drive it. Leave the car at home.

Thank you for the replies. Yes I know it's better to drive it longer distance's. I do try to drive at least 10 -12 miles on each trip to the store, even though the store is only 2 miles away. But on occasion I'll drive it a fifty mile round trip to to next largest town where big stores are. It's the only highway vehicle I own now. When I bought it, me and my wife were somewhat more active in getting out and taking/hauling my jeep places. But things have slowed way down. Nov.6th my daughter and I hauled the jeep to a veterans day parade 60+ miles away. That's about the use of it these days. It was my first diesel to own and I really like it and is difficult to make a decision to trade it in on a gas vehicle.

Take a scenic drive or trade it on a gas F150 that will do the job just fine.

Re-sale right now is really good and you would get top dollar.

Local stop/go driving only, 230-260 miles per regen is about right. If you like the truck, keep it but don't track the MPG because it will be poor and as an optional step, keep track of completion of active regens to keep it healthy. This could lead to early EGR or DPF issues, however just deal with that when it occurs in the future knowing your use case. If the poor MPG or early emissions repair possibilities continue to bother you, a diesel may not be the best equipment. If you like the SD line of trucks vs a half ton, consider the 6.2L or 7.3L. I daily drove my pickup from 2010 to 2018. Active regens averaged 300 miles when new, 250 miles became normal around 50k miles and was as poor as 160 miles by 2018 which I think was around 90,000 miles by then where it was overdue for an EGR cooler replacement.

1300 miles isnt that much, like previous users said you could get up to 10k on a tank depending on how you drive. Your truck will tell you when your due to fillup. DEF is pretty readily available and not too expensive. dont worry about the reading.

It is possible to daily drive the truck and have no problems. When I first bought my truck, my first diesel, I had no clue how finicky the emissions were but consider myself lucky as I live in the hills south of Buffalo. When I drive home, the altitude goes up so I do get some passive regeneration as I drive because the EGTs get hot enough climbing the hills. My regen cycles go out very close to and to 500 miles. It just depends on if I do more stop and go driving in the area where I work. 20 miles for a regen is normal. I've seen as low as 16 miles and up to 28 miles in the past.

Like others have said, it's normal what you are seeing with how the truck is being driven. She needs to get hot and driven awhile to keep the emissions happy. Like I've said, I didn't know any of this when I bought my truck and am lucky as my daily routine and where I live keep my truck in check. Good luck.