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Discussion Starter #1
I was wondering what people's habits are when adding DEF fluid. This is my first diesel that I have had to add DEF and with 15,000 miles I've only filled it up a few times. Got the message again today that it is low, but the previous times I let it go till the warning of speed limitations came on then added. My thinking on this is that since DEF does have a shelf life if I pretty much ran the system out I would have all fresh in compared adding a 2.5 every few thousand or so. Is there any harm in running the tank dry? I know you really don't want to run these newer diesels low on fuel because of potential increased contamination in a low tank. The times I have filled up it has taken five gallons. I have been going to the dealer and getting the AC Delco stuff just in case I ever had an issue. It's more expensive but who cares if it's $5 more I guess. This is my farm pickup so I almost never get 50 miles away from my house so it would be unlikely I'd ever get in a situation where it would actually be speed limited before I could get DEF.
 

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What you're doing 2.5 gals at a time is exactly what I did when all that was on my truck and it worked well, I never had a poor def fluid quality light. I also only used AC delco. My truck didn't get a whole lot of miles put on it on a regular basis, so that's the strategy I used. Wait for the warning message and add 2.5gals. I've seen a lot of dmaxes over in our Chevy shop with the def tanks being pumped out due to poor def quality, people constantly topping them off and or getting cheap def that's been sitting on the shelf too long. I know our chevy parts department purges the def every few months, if it's old it gets tossed. I'd keep doing what you're doing, like I said it worked well for me.
 

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Discussion Starter #3
Yeah my local dealer goes thru a lot of DEF and he keeps it in the back of the shop in a dark area. I have been tempted at times to buy some on sale DEF at the local NAPA or farm store, but there is just no way knowing how old it is. I'm sure it's fine, but you never know.
 

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Another reason to delete DEF lol
 

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I use to add when id get the 1st warning. Use the DEF from the DEF pumps at truck stops. Much cheaper in price at 2.50-2.70$ a gal. Plus its just as fresh or fresher then the jugs from parts stores & dealers.
 

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I use to add when id get the 1st warning. Use the DEF from the DEF pumps at truck stops. Much cheaper in price at 2.50-2.70$ a gal. Plus its just as fresh or fresher then the jugs from parts stores & dealers.
Yeah the margin on that stuff must be insane. I mean it's water and some urea! It cost me $30 for five gallons at my local Chevy dealer. Nuts.
 

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Discussion Starter #8
I'm almost at 6k miles and I haven't had to add any Def fluid yet
Seems like I've been adding every 4-5K or so. I haven't been all that impressed with the mileage, hoped it would be better. So far a lifetime average of about 14. My LMM was usually around 13 so it's slightly better, but was hoping for more. However, the LML weighs about 700 lbs more than the LMM so that does make a little difference I'm sure.
 

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I top mine off about every other week and never let it get low.

One thing I do is shake the DEF container up before adding any. I wipe the cap off to remove any crusted DEF off it before putting it back on.
 

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I usually wait until I get to the 300 miles to derate message and then fill 5 gallons. The dealer filled the truck once and I filled the next two times and I've never had a problem. I get the Blue DEF from my local Sam's Club. They move through it pretty quickly so I know what I'm getting isn't old and it costs about $22 for the two containers.
 

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Does DEF really help the environment? I mean think about it, it comes in a plastic jug and a box. How many people are gonna recycle those? I would say less than 1/2.
 

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Does DEF really help the environment? I mean think about it, it comes in a plastic jug and a box. How many people are gonna recycle those? I would say less than 1/2.
I could be wrong, but I'm pretty sure here in PA if it isn't food grade plastic, we can't recycle it. I know those are at least the stipulations for my recycling pick up. Anything that's in the garage that is in a plastic container (oil, DEF, trans fluid, etc) has to go in the garbage.
 

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I could be wrong, but I'm pretty sure here in PA if it isn't food grade plastic, we can't recycle it. I know those are at least the stipulations for my recycling pick up. Anything that's in the garage that is in a plastic container (oil, DEF, trans fluid, etc) has to go in the garbage.
There ya go. The EPA is saving the air by polluting the ground. Put it in the trash and it will magically "disappear".
 

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Truck stop DEF for me. Ever since I learned about it I go there all the time. Add about 3 gallons every 4K miles or whenever the 29% light comes on. At $2.69 a gallon a heck of a lot cheaper than anyplace else. The Blue Def runs around $6-$7 a gallon in my area. There are date codes on every bottle. You just need to know how to read them. Use the search on this forum or google it. I honestly believe the truck stop def is probably the freshest. The place I go says they get there tanks filled every 10-14 days so it's got to be better than store bought jugs
 

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Some say it is a pain to fill and others not.

I don't find it a pain to fill at all.

I have only added 3.5 gallons in the past 5,000 miles (1 gallon added at last oilt change and 2.5 gallons since)
 

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I think the location to fill the DEF tank could be placed someplace else. Under the hood in the rear corner is sort of a pain but so is pouring 2 gallons of transmission fluid in the dip stick hole. Owell enough of my complaining I guess
 

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Does DEF really help the environment? I mean think about it, it comes in a plastic jug and a box. How many people are gonna recycle those? I would say less than 1/2.
I always burn mine so that it doesn't go to a landfill. :rofl Honestly living in the rural area I do burn waste paper. There isn't much the garbage truck picks up from here to go to a landfill. Glass and metal cans I can take into town to recycle. The only paper I take in is newspaper.
 

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I've only had to refill mine once side I've had the truck. I bought the super tech brand from Wal-Mart. It was only $8 for 2.5 gallons and it has the date on an easy to read sticker. There's a truck stop close to my work so I think I'll swing by there next time.
 
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