DEF addative

[roadrunner16]

I'm thinking about getting a Sprinter RV and have ? about this additive called DEF or DIF.
What's the general cost per gal.?
How much dose it hold?
How often do you have to fill it up? Plus any other info you might have.

[Dakzuki]

lanerd wrote:
You DO know that DEF is NOT a fuel additive.....right? In fact, it's not even an additive as you don't add it to anything. It is used just as it comes out of the jug.

I get mine at Walmart for a little less than $12 for 2 1/2 gallons. My DEF tank holds 13 gallons and I'll usually wait until it gets down to about a half tank (approx 6 1/2 gallons) and I'll buy two of the Walmart boxes (5 gals). I can get about 100 miles to a gallon of DEF.

Don't confuse this DEF with a fuel additive. It does NOT go into the fuel tank as it has its own. The fluid is used in the catalytic converter to increase the temperatures so that it will burn any unburnt fuel in the exhaust system.

After 7000 miles, I can run my finger around the "inside" of my tail pipe and my finger comes out perfectly clean. No soot or carbon what so ever.

Ron

That's not the DEF making your pipe sootless, it's your DPF (Diesel Particulate Filter)

[Dakzuki]

Info here: DEF (Diesel Exhaust Fluid)

[tom076]

I know that flying J on I57 in Illinois just north of Sikeston has def in the tank, problem is that is is located on the opposite side as my tank, would have to enter the wrong way into the pumps, over the road trucks lined up at the deisel pumps, no way for me to get to the pumps, just bought the plastic 2 1/2 gal. Evidently my guage dowes not work properly, shows 1/3 full and could only get about a gallon into it before it overflowed.

[wintersun]

DEF Blue is the most widely available brand you can buy in a store. It is sold at most auto supply stores. Buying DEF in plastic 2.5 gallon containers that are shipped to a retail store is always going to be the most expensive way to purchase it.

Going to the pumps you get quality DEF and it is going to be the freshest. The feds are moving to restrict the capacity of the DEF tanks on the big rigs to insure that it is fresh. The idea will be that the trucks get DEF whenever they stop for diesel, which is no big deal as the trucker can fill both tanks at the same time at the same pump island.

[Sailordive]

aruba5er wrote:
If anyone is still reading this, Mercedes require that you use their DEF. I think it's called DEF BLUE. Was talking to a service man at the chev dealership and he said "don"t complain about our price of DEF, a Mercedes has to have their brand and costs about $75 to fill up" True???

Absolutely not. The dealer told us to buy it at Walmart, it's cheaper. If you take your vehicle in for service they will fill it and charge you that much.

We had a warranty issue that was showing exhaust related. We filled the DEF tank across the street prior to taking it in for service so we would not pay them to top it off.

[brooks379]

Yea DEF is not a fuel additive at all !!! If you put DEF in your fuel you will ruin the fuel system among other things. DEF is diesel- exhaust - fluid and it has it's own separate fill tube and tank.

[wintersun]

Any DEF you can buy meets the manufacturers' requirements. It is only urea in solution. It degrades over time and with exposure to sunlight. I avoid any problems by getting it at the pump at the truck stops where it is cheaper than getting it in a plastic jug and I know when I leave that the DEF tank is full. Some Shell gas stations are putting DEF pumps in the same area as the diesel pumps and these pumps use smaller DEF nozzles which is a big plus.

DEF is consumed as diesel is burned. My truck burns one gallon per 750 miles with a heavy load and without a load it averages around 1000 miles per gallon of DEF.

Best not to store DEF as it has a shelf life of 6 months or less and if you buy it at an auto supply store it may have sat there for a month or longer as well.

[aruba5er]

If anyone is still reading this, Mercedes require that you use their DEF. I think it's called DEF BLUE. Was talking to a service man at the chev dealership and he said "don"t complain about our price of DEF, a Mercedes has to have their brand and costs about $75 to fill up" True???

[CavemanCharlie]

Oil too,,,,, These new diesel engines require there specific oil. If you dump in as little as a quart of the old style oil you have royally screwed it up.

[mlts22]

Bob Vaughn wrote:


We were on our way to Alaska and were in BC and I went in to a NAPA auto parts store to purchase a jug of DEF the clerk warned me not to put it in the fuel tank. When I asked her why she was warning me she replied that the week before they had a guy come in with a new truck and bought jug and poured it into his fuel tank instead of the fill tube for it. He only made it to the corner before his truck quit. He had to purchase a new engine because the warranty would not cover that mistake....

I know someone who bought a new F-350 and did just that -- poured the DEF in the fuel tank. Needless to say, the $17,000 bill to rebuild the engine and a new high pressure fuel pump wasn't a happy thing.

[Bob_Vaughn]

lanerd wrote:
You DO know that DEF is NOT a fuel additive.....right? In fact, it's not even an additive as you don't add it to anything. It is used just as it comes out of the jug.

I get mine at Walmart for a little less than $12 for 2 1/2 gallons. My DEF tank holds 13 gallons and I'll usually wait until it gets down to about a half tank (approx 6 1/2 gallons) and I'll buy two of the Walmart boxes (5 gals). I can get about 100 miles to a gallon of DEF.

Don't confuse this DEF with a fuel additive. It does NOT go into the fuel tank as it has its own. The fluid is used in the catalytic converter to increase the temperatures so that it will burn any unburnt fuel in the exhaust system.

After 7000 miles, I can run my finger around the "inside" of my tail pipe and my finger comes out perfectly clean. No soot or carbon what so ever.


Ron

We were on our way to Alaska and were in BC and I went in to a NAPA auto parts store to purchase a jug of DEF the clerk warned me not to put it in the fuel tank. When I asked her why she was warning me she replied that the week before they had a guy come in with a new truck and bought jug and poured it into his fuel tank instead of the fill tube for it. He only made it to the corner before his truck quit. He had to purchase a new engine because the warranty would not cover that mistake....

[lanerd]

JoeH wrote:

lanerd wrote:
You DO know that DEF is NOT a fuel additive.....right? In fact, it's not even an additive as you don't add it to anything. It is used just as it comes out of the jug.

I get mine at Walmart for a little less than $12 for 2 1/2 gallons. My DEF tank holds 13 gallons and I'll usually wait until it gets down to about a half tank (approx 6 1/2 gallons) and I'll buy two of the Walmart boxes (5 gals). I can get about 100 miles to a gallon of DEF.

Don't confuse this DEF with a fuel additive. It does NOT go into the fuel tank as it has its own. The fluid is used in the catalytic converter to increase the temperatures so that it will burn any unburnt fuel in the exhaust system.

After 7000 miles, I can run my finger around the "inside" of my tail pipe and my finger comes out perfectly clean. No soot or carbon what so ever.

Ron

If you are only getting 100 miles per gallon of DEF , you have a real problem that needs to be addressed.k

Opps... I dropped a digit. Make that 1000 miles per gallon. Stupid finger! 😮 With a little over 7000 miles on my odometer, I've put in 7 1/2 gallons of DEF so far.

[JoeH]

lanerd wrote:
You DO know that DEF is NOT a fuel additive.....right? In fact, it's not even an additive as you don't add it to anything. It is used just as it comes out of the jug.

I get mine at Walmart for a little less than $12 for 2 1/2 gallons. My DEF tank holds 13 gallons and I'll usually wait until it gets down to about a half tank (approx 6 1/2 gallons) and I'll buy two of the Walmart boxes (5 gals). I can get about 100 miles to a gallon of DEF.

Don't confuse this DEF with a fuel additive. It does NOT go into the fuel tank as it has its own. The fluid is used in the catalytic converter to increase the temperatures so that it will burn any unburnt fuel in the exhaust system.

After 7000 miles, I can run my finger around the "inside" of my tail pipe and my finger comes out perfectly clean. No soot or carbon what so ever.

Ron

If you are only getting 100 miles per gallon of DEF , you have a real problem that needs to be addressed.k

[threedogs]

Our 2015 Sprinter gets right at 1000 miles per gallon. It takes 2-1/2 gallons when the DEF check comes on.