DEF usage question

[Camper Ken]

As noted in my signature my 2016 Itasca Navion is on a 2015 Sprinter chassis. There is no DEF level gauge on the dash. How do I know how much DEF is consumed by the miles driven? I realize there is likely some variation depending on the type of driving, etc. I only drive about 1000-1500 miles a year. I've driven almost 1000 miles since it was serviced and the DEF topped off at the dealer last summer. Any idea how much DEF is needed to top it off? Any and all advice is appreciated.

[Lt Dan]

The average DEF usage is 1-2% of fuel burned, which is about 1-2 gallons per 100 gallons of fuel. You just have to figure out your mileage per gallon to determine usage by miles driven.

[Camper Ken]

Originally Posted by Lt Dan

The average DEF usage is 1-2% of fuel burned, which is about 1-2 gallons per 100 gallons of fuel. You just have to figure out your mileage per gallon to determine usage by miles driven.

So help me out here...
I have 1000 since DEF was filled at service visit.
I get 12-13 mpg with my Sprinter motorhome.
Would that figure to a gallon or less of DEF?

[bigb56]

Before the AEM and before I started towing a Jeep my Sprinter would use roughly about a gallon every 1,000 miles, my MPG was a solid 14.7. Since the AEM, and since I now tow a Jeep it has started to use a bit more and my MPG is down in the 12-13 range.

You can check the DEF level with a scan tool app that works with your phone like Autel AP200 if you are tech savvy. Scangauge III also works on some years. There are 3 sensors in the tank and the scan tool will tell you which ones are submerged.

If you are only driving 1,000-1,500 miles per year you might run into aged DEF issues depending on the temperature where you park and how fresh it was when filled. Topping it off with fresh might help but in the long run you need to drive it more or you may have to have the DEF changed out once in a while.

Depending on which tank you have it can be easy or hard to drain/siphon. If it fills from under the hood it is the first tank and the bottom can be a challenge to access for draining and impossible to siphon due to a long skinny filler neck with a one way restrictor in it.

If it fills through a side compartment it's the second tank which is very easy to siphon.

[Camper Ken]

bigb56:
Thanks for the info but don't have a scan tool and not likely to get one. My motorhome is parked in the driveway with summer temps ranging from the 80s to 90s, so I'm aware thus can have an effect on the DEF. I'm not about to try draining it without knowing how to do it on my rig and I can only imagine how expensive it would be to get it done at the dealer. I guess I'll just have to hope for the best. What happens when DEF becomes "old"?

[Airboss68]

Look through your Sprinter owners manual if you have one.
We had a slightly newer model and you should be able to scroll through a menu on your dash to see DEF level.

Also look here>>>>>>>>>>>>>>>>>>>>

https://www.google.com/search?q=How+...hrome&ie=UTF-8

[777 Driver]

A google search for "2015 sprinter def level" shows this:

To check the DEF (Diesel Exhaust Fluid) level in a 2015 Sprinter van, you can use the vehicle's menu system on the steering wheel or check the visual indicator on the DEF container. The DEF level can also be accessed through the service menu on the dash. When the DEF level drops below 10%, an amber warning light will appear.

Here's a more detailed breakdown:

1. Using the Steering Wheel Menu:

Navigate to the "Home" screen on the steering wheel.
Select "Service" on the touch pad.
Swipe down to "DEF" to view the current level.

I'll admit that I've never been in a 2015 Sprinter, so, I have no idea whether it's accurate. But, it should be pretty easy to try.

Take care,
Stu

[Camper Ken]

To Airboss 68 and 777 Driver:
The method you recommend does not work on a 2015 Sprinter. Steering wheel menu options are different. Thanks anyway.

Anyone with a 2015 Sprinter know if it's possible to access DEF level?

[johninsd]

I have a 2016 Navion G on a 2015 Sprinter chassis and use a Scangauge which does show the DEF level as "RTL" (Reagent Tank Level). The level shows as a percentage. I have found that if the percentage gets down to about 40 I can then put in a full 2.5 gallon box of DEF and the percentage returns to near 100. 96,000 miles so far and all is well. I've never found any way to check DEF other than using the Scangauge.

[Camper Ken]

Originally Posted by johninsd

I have a 2016 Navion G on a 2015 Sprinter chassis and use a Scangauge which does show the DEF level as "RTL" (Reagent Tank Level). The level shows as a percentage. I have found that if the percentage gets down to about 40 I can then put in a full 2.5 gallon box of DEF and the percentage returns to near 100. 96,000 miles so far and all is well. I've never found any way to check DEF other than using the Scangauge.

What scangauge do you use? Where can I buy one and how do I use it in my Sprinter?

[TomD55]

I use

https://www.amazon.com/FIXD-Professi...mFtZT1zcF9tdGY

Not sure if it checks DEF levels. It's from Amazon and if it doesn't work, you send it back. Plug it in to the diagnostic plug in the fuse box area. App goes on your phone. I do not pay for the premium system.

[CWSWine]

Originally Posted by Camper Ken

bigb56:
Thanks for the info but don't have a scan tool and not likely to get one. My motorhome is parked in the driveway with summer temps ranging from the 80s to 90s, so I'm aware thus can have an effect on the DEF. I'm not about to try draining it without knowing how to do it on my rig and I can only imagine how expensive it would be to get it done at the dealer. I guess I'll just have to hope for the best. What happens when DEF becomes "old"?

Not sure what a Sprinter does but I put some bad DEF in my truck I had and limited the speed to 20MPH and limited mileage till correcting the problem. I went to Harbor Freight and bought a hand pump and pumped out the tank and replaced it with known good DEF. I couldn't get every drop out but enough that the sensor didn't sense that the DEF was bad.

I used a 2.5 gallon purchased at a large chain store and the seal was broken and I think that was the bad DEF. If the seal not intact don't use.

Here a link to one that should work
https://www.amazon.com/Antifreeze-Tr...zcF9tdGY&psc=1

[johninsd]

Originally Posted by Camper Ken

What scangauge do you use? Where can I buy one and how do I use it in my Sprinter?

I use the Scangauge II but if I were to buy another one I'd probably get the Scangauge III. They are available from Amazon or the Scangauge website and several other places as well. Installation involves finding a place to mount it and plugging it in to the OBDII connector. With the Scangauge II you have to enter the "X-Gauges" , which are specific to each vehicle model, manually, the Scangauge III finds them automatically, saving some time and frustration. I mounted mine on the dash just above the speedometer using self stick velcro tape.



Scangauge website is here - https://www.scangauge.com/

[wgiff]

bigb56, reference the skinny filler neck...do you know if the one way valve in the tank or in somewhere in the filler neck ?

thanks,
wgiff