DEF CONSUMPTION

[jessej]

Well folks, ran 4000 miles in 3 weeks and my dash said 800 miles till def empty. It took 5 gallons to fill it up. 5 gallons in 4000 miles? Seems like alot to me. Anyone else have any input. Also, low tire pressure light comes on at anything less than 80psi, 60 psi makes it ride a lot smoother, but ford says they cant recalibrate the sensors for liability purposes. My after market wheels are only rated at 60psi anyway. Any input on that subject would also be greatly appreciated. Also, can anyone give me some real life experience with a spartan system on a 6.7?

[a2elvis]

From what ive heard and seen its about 1000 miles per gallon of DEF. Once again the feds have got involved in another portion of OUR trucks! Freakin tire pressure sensors!! Really? Its fine and all for mama drivng the caravan, but I think we can check our tires ourselves. Not sure how to get around that. Im sure if you found the right dealer they could disable the TPMS, just not sure who?

[CascadeF250]

Originally Posted by jessej

Well folks, ran 4000 miles in 3 weeks and my dash said 800 miles till def empty. It took 5 gallons to fill it up. 5 gallons in 4000 miles? Seems like alot to me. Anyone else have any input. Also, low tire pressure light comes on at anything less than 80psi, 60 psi makes it ride a lot smoother, but ford says they cant recalibrate the sensors for liability purposes. My after market wheels are only rated at 60psi anyway. Any input on that subject would also be greatly appreciated. Also, can anyone give me some real life experience with a spartan system on a 6.7?

Others have said that a Ford dealer can change the setting in the computer to recalibrate for lower tire pressures. From what I understand not all dealers are willing to do this. My truck was not filled fully by the factory or dealer from the start. My first def fill was free from my dealer. They had to add DEF at 6000 miles. The rate of DEF usage can depend on how much towing you do and also your style of driving. I seem to use about 5 gallons in 7000 miles with how I use my Truck. I have close to 14,000 miles on it and when the less than half full warning comes on I put in 2 1/2 gals. (My tire sensors came set at 60 pounds by the way).

[bajasst]

The most amazing thing to me is. I brought my truck in to get the DEF filled because I got a coupon from Ford for the first fill free. According to the computer I had 400 miles left but the dealer told me it only took two gallons. Bet you when I fill it it will take 5 gallons.

[Ryan Rønning]

I bet it will too if your dealer is anything like mine.

[bajasst]

Probably billed Ford for 5 gallons also.

[jessej]

I wander if i can gut under there and pinch that def injecter line? As long as the def tank is full wouldnt the computer be happy?

[Ryan Rønning]

Thats some uncharted territory. I wouldn't.

[s8v4o]

Originally Posted by jessej

Well folks, ran 4000 miles in 3 weeks and my dash said 800 miles till def empty. It took 5 gallons to fill it up. 5 gallons in 4000 miles? Seems like alot to me. Anyone else have any input. Also, low tire pressure light comes on at anything less than 80psi, 60 psi makes it ride a lot smoother, but ford says they cant recalibrate the sensors for liability purposes. My after market wheels are only rated at 60psi anyway. Any input on that subject would also be greatly appreciated. Also, can anyone give me some real life experience with a spartan system on a 6.7?

As someone already mentioned 80 psi isn't the trigger point. I think the number is closer to the 50-60 psi range.

Originally Posted by a2elvis

From what ive heard and seen its about 1000 miles per gallon of DEF. Once again the feds have got involved in another portion of OUR trucks! Freakin tire pressure sensors!! Really? Its fine and all for mama drivng the caravan, but I think we can check our tires ourselves. Not sure how to get around that. Im sure if you found the right dealer they could disable the TPMS, just not sure who?

I don't believe they can be turned off. What you can do though is what some of the mustang guys do. You can remove them and install them in a home made container. What you do is get some 3" PVC tubing lets say 6 inches long. Drill a hole in one of the end caps for a valve stem so you can air it up. Install one of the caps with PVC sealant. Put the sensors in it. Put the other cap on. Then simply air up the unit to 80 or so psi. It's really easy to make and it works.

Originally Posted by jessej

I wander if i can gut under there and pinch that def injecter line? As long as the def tank is full wouldnt the computer be happy?

No the computer WILL NOT BE HAPPY. The purpose of the SCR system is to reduce NOx. "Small quantities of diesel exhaust fluid (DEF) are injected into the exhaust upstream of a catalyst, where it vaporizes and decomposes to form ammonia and carbon dioxide. The ammonia (NH3) is the desired product which in conjunction to the SCR catalyst, converts the NOx to harmless nitrogen (N2) and water (H2O)."

The PCM looks to the sensor that reads the amount of NOx to see if it's doing it's job properly and so it knows how much DEF to inject. If you pinch the line it's possible the PCM will put you into a limp mode and you won't be able to drive more than 55mph. This allegedly happens if you completely run out of DEF. I haven't ever ran completely out so I can't confirm this. But I think "pinching the line" may give the same results.

[ups 6.0]

Originally Posted by jessej

Well folks, ran 4000 miles in 3 weeks and my dash said 800 miles till def empty. It took 5 gallons to fill it up. 5 gallons in 4000 miles? Seems like alot to me. Anyone else have any input. Also, low tire pressure light comes on at anything less than 80psi, 60 psi makes it ride a lot smoother, but ford says they cant recalibrate the sensors for liability purposes. My after market wheels are only rated at 60psi anyway. Any input on that subject would also be greatly appreciated. Also, can anyone give me some real life experience with a spartan system on a 6.7?

DEF fluid usually will last me around 7500 mi before the 800 mi warning comes on.And if you look in the owners manual,there is an instructions on how to retrain your tires.