DEF - What is it and how do you use it

What is this stuff (diesel exhaust fluid) and why you need it. Diesels made since 2010 require this for emission control and will go into a limp mode if you run out. How far can you go without re-filling? Peak Blue DEF date code revealed

[@nerdinium]

The reason you were getting leaking during the pour is because the little black rubber thing on the DEF spout cap should be above the hose. It lets air back into the box for a smoother pour.

[@BrokerDon]

Another awesome video Ron !!! Thanks! FYI owners of 2011 Winnebago View model 24K like ours has the filler in the passenger side basement compartment in front of the right rear dually wheels, NOT under the hood. Refilling using the 2.5 gallon DEF jugs requires "MacGyver-ing" TWO of the plastic fill hoses together which really makes this a 2-person job... or going to a truck stop that has DEF pumps. You also have to unlock the DEF cap to remove it using the small U-shaped "key" that's stored with the jack and tools under the passenger's footwell. Definitely glad Mercedes made this easier on later model Sprinter RVS like yours.

[@ontheroadwithron2432]

Sound a PITA to fill yours. Only good point is you have one of the largest tanks,

[@BrokerDon]

@@ontheroadwithron2432 DEFINITELY a PITA to fill our 2011 Winnebago View 24k's DEF tank. Somebody has to hold the DEF tank door up as high as it will go to empty the 2.5 gallon DEF jugs. Just using the Winnebago DEF door hold up doesn't work. We look at refilling our DEF tank as an opportunity to do DEF Yoga since my ex-gymnast wife and I have to "hold the pose" to refill our DEF tank... and there is absolutely no way NOT to spill any DEF while doing it. Our Mercedes "Engineered Like No Other" DEF system as DEFinitely designed by engineers who never actually tried to fill it. HUGE Mercedes Benz FAIL

[@ontheroadwithron2432]

Maybe you cold find a small pump to suck it out of the jug. The DEF is not hazardous and should not bother plastics.

[@BrokerDon]

@@ontheroadwithron2432 Hmmm... That might be worth a try.

[@paullange954]

Thanks for the explanation. Good summary of DEF which isn't available with the engine info. Paricularly the date of manufacture

[@ontheroadwithron2432]

Don't like that difficult date code for a product that has a shelf life. Why make it so hard.

[@klam77]

Volkswagen brought us here!

[@GrahamParkerVermont]

Love it Ron!

[@rafski123]

Costco Business Center also sells DEF jugs

[@craigwilson1284]

Ron, thanks for the info on DEF but How often due you change your motor oil?. Ordered 2018 sprinter, should be taking delivery soon.

[@ontheroadwithron2432]

First was at 17,000 miles. Second will be when I get back. It will be around 36,000 miles then. I do all long freeway trips and that is pretty easy on the oil. I’ll be doing a video on my schedule B maintenance as I do it myself.

[@renepasquale2248]

I do not think i will be doing any traveling in the foreseeable future. Considering the 2-year shelf, how do you drain/replace the DEF tank?

[@ontheroadwithron2432]

Never had to do that. It might have a drain plug or just use a hose to siphon it out.

[@winebox]

Since this stuff has a shelf life wouldn’t it be better to fill it at a truck stop to get fresh?

[@ontheroadwithron2432]

winebox you certainly can but it’s not necessary. Walmart is more convenient for us as we stop there to resupply quite often and don’t stop at truck stops unless we have to. A lot of the times we have to go into the store to pay and I’d rather use the pay at the pump at regular gas stations. I burn through a box every 4-5 months so shelf life is not a problem for me.

[@georgek719]

Have you had any issues with the Mercedes-Benz and their limitations on biodiesel, particularly as it affects the engine warranty?

[@ontheroadwithron2432]

I have not had any warranty work done, but occasional use does not seem to be a big problem unless it gets below freezing. I have more info on the Diesel video. kzbin.info/www/bejne/bWSye3Wngc-AhNU

[@klam77]

i can't believe you drank it! OMG!@Q

[@ontheroadwithron2432]

Ha ha. Well I tasted it. Very bitter but not hazardous.

[@peterahkinglau5085]

Ron: Do you /should you drain the DEF in the winter? I live in Los Angeles, CA, and some nights the temperature goes below freezing. Will the DEF freeze and harm the engine? Thanks. Old Man Peter

[@ontheroadwithron2432]

Peter Ahkinglau DEF freezes around 12 degrees. I never drain mine. Freezing will not hurt it anyway. Mercedes has a heater in the tank so you can drive in very cold weather.