Finally got around to getting a new truck. Basically went with the same thing I've had, and got another 3/4 ton Duramax LTZ. Got the LTZ because I hate painted bumpers and like chrome - like all us old guys do. Really like the truck, and how it runs. Only has 2200 miles and got 21.6 mpg from here to Baton Rouge. Just came out of an 08' Duramax and it seems a little stronger than that one, even though it had a Hyper Tech tuner (at least in stage one).

The only complaint is, who in the heck decided where to put the DEF filler? It's under the hood right against the windshield, and over one of the batteries. That's one of the dumbest designs I've ever seen. Used 3 jugs so far, and have spilled it on the battery twice. It seems very corrosive because it dries into a white gunk that has to be washed off. What a pain. Did Ford patented putting it by the fuel filler neck. Dumbest thing I've seen in a long time.

Wondering how everybody else fills theirs without getting it on everything. Maybe start carrying a funnel and rag.. By the way, I'm using the Bucee's brand DEF. If the Delo or other has a better spout, I may have to go that way.

You've gone through 3 - 2.5 gallon containers of DEF in 2200 miles?

My Ram's DEF is right by the fuel filler also. That's a bad design for sure.

I deleted mine.

Many of the trucks are not shipped with a full tank of def.

Have you tried filling at one of the DEF pumps? It may be easier.

I know some people hate to pop the hood on their trucks but it may be a good thing. There was a post on another forum last year about a guy accidentally pouring def in his fuel tank on his f250. Turns out this is a very common expensive mistake.

Id say its more of a very expensive mistake and marginally common.

Im the biggest GM/Duramax fanatic there is.. BUT, I'll give it to Ford/Ram.. At least they were smart enough to put the DEF filler by the fuel tank...... Stupidest thing I've seen from GM in a while.

On the other hand, what year did you get? I actually went to Ron Carter Chevy earlier to test drive a 2019 L5P for just [censored] and giggles. They have some power! But, my '06 does the job just fine for now

We get a least a couple customers a year that fill their cars with diesel. They have to hold the larger filler tube against the smaller filler neck and it must take a long time to fill with it shutting off constantly. They will fill them up do that . They also blame it on their wives .

I'll admit it's not the easiest place to fill but it's not as dumb as some think.

You can't tell me you're too stupid to see the difference between the blue cap that says DEF, and the green cap that says DIESEL. But then again, it is 2018...

(Not directing this comment toward you, talking about people in general)

Another question about DEF on the new trucks , have a 2017 Denali , Duramax , The tank for DEF is in a strange location , if you don�t have running boards it looks like a mistake . I heard some talk about DIY relocating it .

If you're dumb enough to put DEF in your fuel tank you probably shouldn't be driving. I know it happens but there is no excuse and no one to blame. My dealer (Planet Ford) never fills my DEF up even though it's included in my maintenance plan I paid for when I bought the truck. I've left the dealership two times and had the low DEF light come on while driving home and the paperwork showed that they had filled it. Last week the excuse was " I didn't ask for it". I told the manager I didn't ask for the tires to be rotated, oil filter replaced, tire pressure checked, etc. but they put down they did it on the paperwork.

I'll be extra careful next time filling up my DEF tank after making that comment, don't want to be "that guy" putting DEF in their fuel tank.

DK, I got a new 18' and really like it. I was back at the dealer last week, and they had a new 1/2 ton on the showroom floor. Noticed that the fuel filler door was rectangular, so I opened it. This one was a gasser, but there was a round rubber knock-out plug where a DEF filler neck might go.... Bet they moved it there for the 19's. At least for the 19 1/2 ton diesels.

Honestly I don't think having the DEF filler under the hood would bother me at all. I fill mine once every 10,000 miles or so, so its no biggie, its not something that sneaks up on you all of a sudden you know like a month in advance the gauge reads near empty lol.

I do not like the placement of the tank on the GM's I would have broke one of those by now.

I�ve got a 2016 Chevy Silverado and agree that the DEF fill is a pain to fill being under the hood. What I�ve been doing is having the DEF filled completely every 3000 miles when I change my oil. Very rarely do I have to carry an extra DEF container except for cross country road trips!

3k mile oil changes?

This! I have a 2015 Duramax. I drove 35 miles to the nearest DEF pump for the longest time. Luckily, about 6 months ago they put one in at my nearest gas station. Not only is it 100x easier, they also charge less per gallon out of the pump. If you don't know where the nearest DEF pump is, try locating the nearest pump on this website, just make sure to select to search only pump locations: https://www.discoverdef.com/retail-def-search/ It doesn't show every single DEF pump location, but it shows the vast majority.