Adding DEF

[blackdragon3]

New to this DEF Stuff. Previous RV not necessary. SO How often, ?Mileage?
When light comes on? Every fill up? Tks in Advance.

[MTK46]

First of all Welcome. There should be a gauge for the DEF. You will find that it goes along ways before needing to refill. I don't have DEF in my MH but do in my F-350. When towing with it and a seven gallon tank it would need DEF after 3000 miles. Only take 2-3 gallons.

[Matrixxdg]

Originally Posted by blackdragon3

New to this DEF Stuff. Previous RV not necessary. SO How often, ?Mileage?
When light comes on? Every fill up? Tks in Advance.

Hi BD3. I am pulling with a Dodge Ram 2500 but all diesels are the same. You should have a DEF gauge on your dash that tells you when you are getting low. I usually get 3500- 4000 miles before it hits 1/2 full. I rarely let it get below half. Half full is usually 2.5 gallons at about $20.00. If you let it run out the vehicle will slow to about 10 mph until you fill it. This is experience talking.

Hope it helps...MG

[lanerd]

Keep in mind DEF has a shelf life of about a year or so. Since we only travel about 4000 miles a year, I usually will keep my DEF tank at about 1/2 tank (I3 gal cap) and add a 2 1/2 gal jug from Walmart ($7.88) when it gets down closer to 3/8 tank. Those who travel more often will keep their DEF tank up close to full and fill occasionally.

You can get DEF at just about any truck stop (inside in jugs or outside at the pump). Obviously, at the pump will be the easiest and cheapest.

Ron

[Loggenrock]

FYI - not all Sprinter chassis' have DEF gauges... Mine doesn't. My calculations are about 1 quart every 450 miles. When the ADD DEF light comes on, you need to put in at least 2.5 gallons to get the light to reset. No harm to wait until dash indicator comes on - I just tend to keep the tank topped off. Believe Sprinters have about a 5-6 gallon DEF reservoir.

[vsheetz]

Wal-Mart has DEF for $7.88 a 2.5 gallon jug. As good as any other DEF.

To make it go in easier and faster: use a good funnel as appropriate for your vehicle, not the tube that comes with each jug. Poke a vent hole in the top of the plastic jug to enable it to readily and smoothly pour.

[luvlabs]

The official Sprinter DEF capacity is 4 gallons. MB started adding a DEF gauge to the 2016 chassis that is available through the steering wheel buttons and the DIC. I add DEF when it gets one half on the gauge.

[User1011]

Originally Posted by luvlabs

The official Sprinter DEF capacity is 4 gallons. MB started adding a DEF gauge to the 2016 chassis that is available through the steering wheel buttons and the DIC. I add DEF when it gets one half on the gauge.

Not sure this is correct information. Our 2014 Chassis (2015 LTV Unity) has a 3.2 gallon DEF tank. I believe this was standard at the time.

[gchapell]

2016/ w2015 Chassis. Light came on at 7600mi. Took the whole 2.5 gal. Will have to research tank capacity. I believe there is a screen on the nasty(Not user friendly) dash control display like you can check oil level.

[User1011]

Originally Posted by gchapell

2016/ w2015 Chassis. Light came on at 7600mi. Took the whole 2.5 gal. Will have to research tank capacity. I believe there is a screen on the nasty(Not user friendly) dash control display like you can check oil level.

The DEF tank capacity is in all likelihood 3.2 gallons.

[Gary CA]

Beware of a DEF from Walmart. Friend bought a jug, took it outside and the seal was open; DEF was gone and refilled with water. He checks the seals under the cap before purchase. Walmart took it back and he was told the water refill happens often.

[vsheetz]

Originally Posted by Gary CA

Beware of a DEF from Walmart. Friend bought a jug, took it outside and the seal was open; DEF was gone and refilled with water. He checks the seals under the cap before purchase. Walmart took it back and he was told the water refill happens often.

Agree. Check to endure sealed. If not sealed do not buy. Not just Walmart DEF - any brand anywhere.

This type of thing happens with many similar products. RedGard - used to waterproof a bathroom shower before tiling. Relatively expensive. Buy a gallon, use half, refill with water - return to Home Depot, Lowes, etc.

[SSTraveler]

I found this spill proof filler hose on Ebay, http://www.ebay.com/itm/Filler-Hose-...QAAOSwTuJYrGJ-. It screws on to your DEF tank and has the spill proof, push type, Kruse filler and other end fits standard US 1 and 2.5 gallon containers or has the adapter for Euro containers like from MB, VW etc. I refill and use the Kruse 1/2 gallon bottle to top off the DEF at home, but I was looking for something that would make it easier to fill the DEF tank on the road. I can carry this and buy a gallon anywhere when I want to top off, fill and go. I've had trouble with my NOX sensor when I have waited and let the DEF low alert tell me when to add DEF. A Mercedes service tech said lots of NOX sensor replacements when you don't keep DEF tank topped off. So I make sure and top off at home and when on a long trip I add a gallon every 1500 miles. The 3.2 gallon DEF tank on a MB Sprinter alerts for refilling between 3000-4000 miles and then it takes the typical 2.5 gallon container to fill up. So a gallon every 1500 miles keeps it topped off nicely.