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Talk to me about the DEF system

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I’m hoping to see my JT Diesel in a few days and realize I don’t know anything about the DEF system. My last diesel was an Audi A3 without the DEF, and, well we know how that story ended up. Where’s the best place to buy DEF? Is there good vs. bad DEF? in doing research, I thought I saw gas stations that you can pump DEF from the pump? I’ve never seen or noticed this before. Any watch Outs?
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I haven’t had my diesel Gladiator long enough to need to do anything with DEF other than top it off (had about a 1/2 tank when we bought it new). However I’ve been driving a 1/2 ton Silverado with the 3 liter turbo diesel for 6 months now. Just shy of 10k miles (9700 and change) and I’ve just scheduled my 2nd oil change. In that time it’s basically used a full tank of DEF. it was at about 1/2 at 5k and about the same now. The dealer topped the tank as part of the 5k service and I’ll assume the same this week. It’s not really a big deal. I did buy a container of Blue DEF and topped off the Gladiator as I didn’t like seeing it low.

Also, I had no issues with the Chevy during the cold weather in January/February. No DEF freeze and I didn’t even plug in the block heater. Truck started every time even in negative temps.
 
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Slojo

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If you download the 2021 JT user manual you can read the maintenance schedule. Basically top it off each oil change. Doesn't mean it is empty just a good reminder to keep it up.
 
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I see 2.5 Gallons on DEF at my local auto store. Platinum for. $23 and regular for $16. is there really a difference? At a difference of $7, that’s cheap insurance if it actually is better.
 

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With the Eco Glad you'll go about 2000-2500 miles before you go down to a half tank of DEF. I like to fill it once it hits a half tank because one DEF container will fill it perfect without any left over. Watch out for spilling, it dries fast and leaves behind crusty white flakes similar to dried salt (which it essential is similar to). Don't sweat it too much though because it washes off and desolves easily with water. The DEF containers are where the problem areas are when it comes to DEF IMHO, but once you learn how to pull off the safety barrier without ripping it to pieces and screw the corrugated hose on correctly you've all but mastered the first hurdles. The next is balancing the container in an area where it hopefully doesn't drip on your clothing while you're carefully pouring it in your Jeep.

Buying DEF for the Jeep is 50x easier than finding the proper oil and filter for a reasonable price. DEF can be found in a multitude of places (even in truck stop pumps) and all you really have to do is keep an eye out for who carries it for the lowest price. There are now two predominant options for DEF both are of the Blue name brand but they now offer a more expensive iteration that they advertise as "Improved".

A couple side notes or words of wisdom for you:
The diesel fuel filler door is of a medium slotted size so you cannot directly fill from the larger or smaller size nozzles (sort of). The door is sized for the most common passenger vehicle fuel station diesel nozzles... I'll explain. With either one you'll find you actually can fill up if you're in a pinch by locating the special fill funnel located under the rear seat. I would try to mentally make note of where it is once you buy the Jeep because there's a pretty good chance one day you'll need it. You see, the filler door has a locking mechanism which is designed to prevent you from mistakingly filling your Jeep with gas (smaller size nozzle) but the engineers didn't account for gas station workers who don't account for exact nozzle sizes and who may accidentally put a gas size nozzle on a diesel pump hose (Happened to me on a long trip with no other stations around). For some reason the filler door is also designed smaller than the big truck nozzles. The only reason I can think of is to prevent filling of high sulphur diesel fuel. What ever the reason they designed it that way at least they give you an option to override. The option is the funnel. It's the perfect size to prevent the door from locking shut for small nozzles and will give you a large opening to spill in with the big ones.

Good luck and enjoy!
 
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With the Eco Glad you'll go about 2000-2500 miles before you go down to a half tank of DEF. I like to fill it once it hits a half tank because one DEF container will fill it perfect without any left over. Watch out for spilling, it dries fast and leaves behind crusty white flakes similar to dried salt (which it essential is similar to). Don't sweat it too much though because it washes off and desolves easily with water. The DEF containers are where the problem areas are when it comes to DEF IMHO, but once you learn how to pull off the safety barrier without ripping it to pieces and screw the corrugated hose on correctly you've all but mastered the first hurdles. The next is balancing the container in an area where it hopefully doesn't drip on your clothing while you're carefully pouring it in your Jeep.

Buying DEF for the Jeep is 50x easier than finding the proper oil and filter for a reasonable price. DEF can be found in a multitude of places (even in truck stop pumps) and all you really have to do is keep an eye out for who carries it for the lowest price. There are now two predominant options for DEF both are of the Blue name brand but they now offer a more expensive iteration that they advertise as "Improved".

A couple side notes or words of wisdom for you:
The diesel fuel filler door is of a medium slotted size so you cannot directly fill from the larger or smaller size nozzles (sort of). The door is sized for the most common passenger vehicle fuel station diesel nozzles... I'll explain. With either one you'll find you actually can fill up if you're in a pinch by locating the special fill funnel located under the rear seat. I would try to mentally make note of where it is once you buy the Jeep because there's a pretty good chance one day you'll need it. You see, the filler door has a locking mechanism which is designed to prevent you from mistakingly filling your Jeep with gas (smaller size nozzle) but the engineers didn't account for gas station workers who don't account for exact nozzle sizes and who may accidentally put a gas size nozzle on a diesel pump hose (Happened to me on a long trip with no other stations around). For some reason the filler door is also designed smaller than the big truck nozzles. The only reason I can think of is to prevent filling of high sulphur diesel fuel. What ever the reason they designed it that way at least they give you an option to override. The option is the funnel. It's the perfect size to prevent the door from locking shut for small nozzles and will give you a large opening to spill in with the big ones.

Good luck and enjoy!
Appreciate the detailed response. When the DEF manufacturer claims “improved”, that just means improved cleaning of emissions? Which would lead to decreased parts failure? It can’t mean improved performance of the vehicle, right? Sorry
if that’s a dumb question.
 

Saltymedic

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Appreciate the detailed response. When the DEF manufacturer claims “improved”, that just means improved cleaning of emissions? Which would lead to decreased parts failure? It can’t mean improved performance of the vehicle, right? Sorry
if that’s a dumb question.
Lol, exactly!!

Blue DEF platinum has a video available to answer those questions better than I could.
 

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So I worked at one time at the worst place on earth as far as companies go. They made def there. A lot of the stuff you see in Walmart, auto parts stores and the such are all made at that same plant in Reno. Just re-bottled and sold under a different name. Same goes for windshield washer fluid. Same shit different bottle.
 
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So I worked at one time at the worst place on earth as far as companies go. They made def there. A lot of the stuff you see in Walmart, auto parts stores and the such are all made at that same plant in Reno. Just re-bottled and sold under a different name. Same goes for windshield washer fluid. Same shit different bottle.
Or is it same ’Piss’ different bottle. ????
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