Buy quality blue def

[Ccrew]

OP touched on it, everyone missed it in the DEF war. Reality is DEF gets old and when it does it crystallizes. At the end of the day it’s just piss (urea) and the biggest thing that causes these issues is the vehicle sitting unused.

[alrothel]

Thats what I used to get for mileage. I had a 2019 F250 Ford with the 6.7 turbo diesel and got about 5000 miles to a tank full. That's about 1000 miles to a gallon of DEF. Now I have a 2020 F-350 with the same motor but get about 1000 to a tank. That like 200 miles to a gallon. The dealer just says that if I tow an RV or anything of weight that's what you get. Now my new RV is a little heavier but that much of a difference?
Is anyone getting that kind of mileage when towing using DEF. I also understand DEF is DEF and paying twice as much for Blue DEF just does not seem justified.

[Ccrew]

Originally Posted by alrothel

Now my new RV is a little heavier but that much of a difference?
Is anyone getting that kind of mileage when towing using DEF. I also understand DEF is DEF and paying twice as much for Blue DEF just does not seem justified.

I have a 2019 3500 Duramax. It lives to tow a trailer, so it's rarely detached, we travel extensively. I questioned my DEF usage at my first service where I had used 43 gallons in 8k miles. Dealer found it "questionable" and escalated to GM. GM considered it normal. Now have almost 40k on the truck, and generally speaking it's a tank of DEF (7 gal) every 4 tanks of fuel, which for us is 12-1500 miles. That's a comparison if it helps. I run the Wal-Mart DEF with never an issue.

[JRTJH]

Originally Posted by alrothel

Thats what I used to get for mileage. I had a 2019 F250 Ford with the 6.7 turbo diesel and got about 5000 miles to a tank full. That's about 1000 miles to a gallon of DEF. Now I have a 2020 F-350 with the same motor but get about 1000 to a tank. That like 200 miles to a gallon. The dealer just says that if I tow an RV or anything of weight that's what you get. Now my new RV is a little heavier but that much of a difference?
Is anyone getting that kind of mileage when towing using DEF. I also understand DEF is DEF and paying twice as much for Blue DEF just does not seem justified.

I wonder if your DEF system is going into regen too often? There may be an issue with the catalytic converter/filter being blocked, causing the O2 sensors to believe it's full and needs regen ???? I haven't heard of anyone using that much DEF unless there's a problem. My "older F250" (2015) uses about 1 gallon per 1500 miles and when towing, the exhaust system gets hotter than when driving solo, so it doesn't seem to go into regen as often, meaning less DEF use when towing. At least that's what I've seen on my truck...

I think I'd find another dealership and let their "diesel experts" do a system check. I don't believe you should be using that much DEF...

[MJCougler]

Thanks all for this info. I too have a 2018 Ram CTD. I never thought about ensuring the DEF has a (foil?) seal. I usually purchase the 2 gallon jugs, and also read about the shelf life and to keep stored in a cool place. I found a diesel truck parts store in my area that sells two jugs in a brown box for a good price and he will also sell one jug if that is all you want (to keep it fresh).

Is it possible, that truck stop DEF at the pump is susceptible to condensation and by only pumping 2 gallons, there could be a higher concentration of condensation (water)? That might be why sealed jugs are a better option. And, only purchase the jug you keep in the in the RV when your gauge is down to a half.

It is cold outside here in NY, so I think I will drive my truck soon for the next errand. mjc

[bobbecky]

The DPF system (diesel particulate filter) is what goes into REGEN. The DEF system continuously injects the fluid into the converter depending on the NOX sensors, one ahead of the converter and one after the converter, which tells the computer how much DEF fluid to inject to control the NOX level coming out of the exhaust. These are two separate systems. It is very possible the sensors are not working properly. We had one totally fail last year, and they replaced both of them, then had to calibrate them. It does seem like we are using less DEF now since that repair was done.

[travelin texans]

Originally Posted by Ccrew

I have a 2019 3500 Duramax. It lives to tow a trailer, so it's rarely detached, we travel extensively. I questioned my DEF usage at my first service where I had used 43 gallons in 8k miles. Dealer found it "questionable" and escalated to GM. GM considered it normal. Now have almost 40k on the truck, and generally speaking it's a tank of DEF (7 gal) every 4 tanks of fuel, which for us is 12-1500 miles. That's a comparison if it helps. I run the Wal-Mart DEF with never an issue.

Using 43 gallons in 8k miles, you've gotta problem, not sure it could leak that much that fast.
My '13 used a 2.5 gallon jug about every 3500 miles, towing didn't seem to increase usage, but it was our daily driver & was towing approximately 50%+ of the time.

[Learnites]

2015 duramax had to replace the Def heater twice in 65000 miles under warranty.

[jasin1]

This video explains a easy fix for ram trucks

https://www.youtube.com/watch?v=JpL_AFttdXc

[jertour]

I purchased what they call refractometer ( I think ) and test the def before
i use it. The meter is made for DEF. It lets you know if the def is good.

[gearhead]

^ good info

[ewbldavis]

A learning experience for me reading this.

Makes me DEF glad I have a gasser (sorry...I'll see myself out)

[notanlines]

^^^^186 miles per gallon is about five times the average usage we read about. Our F-450 when towing uses about one gallon in 850-900 miles.

[Javi]

Originally Posted by notanlines

^^^^186 miles per gallon is about five times the average usage we read about. Our F-450 when towing uses about one gallon in 850-900 miles.

My 2015 F350 uses an average of 2.5 gallons per 3100 miles over the past 6 years and 68,000 miles
When towing which is about 25% of the time it will drop to about 2.5 gallons per 2,000 miles and when not towing it rises to as much as 3700 miles..

For some reason I've kept an Excel spread sheet on fuel mileage, DEF usage, oil changes, tire rotation, tire replacement, filter changes and even battery replacement....

[Bandit12]

FWIW, I work in auto parts sales and I own a 28 Ram with the CTD so yes I use DEF. On our vacation trip last summer, I made sure the DEF tank was full before leaving home. We towed our 4000 lbs Jayco to Rapid City SD from NE Calif, a distance of roughly 1300 miles. We ran around for 9 days, putting a further roughly 600 miles on the truck without the trailer. My DEF gauge was reading 1/2 so I added another 2.5 gal jug before hooking up to head home. We towed the trailer back thru Wyoming to Hill AFB near Ogden UT, A distance of roughly 600 miles and used the same half tank of DEF. Filled up while in UT, traded the Jayco on on a Cougar the weighs about 2000 lbs MORE than the Jayco we had been in and towed the new trailer home, a distance of roughly 600 miles, using about 1/4 tank of DEF. Why the difference? Well, all the way across Wyoming, we were bucking about a 30 MPH headwind the entire trip. The harder the truck is working, the more DEF is used, just as more fuel is used. After talking with my regular wrench that I have service my truck, he explained to me that I need to treat DEF like milk. It will spoil. He advised that I wait until the DEF LOW light comes on, then refill the tank. According to my manual, the tank holds 5.5 gallons. When the light comes on, it will take 5 gallons, or 2 jugs.

[goodellj]

I always get my DEF at truck stops. 125,000 miles, 8 years. Me and all the truckers would be really angry if the DEF from the pump caused a problem. I usually go to Pilot/Flying J. I measured my DEF mileage a few times and found that I got about 2,200 MPG towing and maybe twice that solo.

[K_N_L]

On my 2015 - generally towing 90% of the time, about every 1200-1400 or so miles it will issue the first warning. Typically it will take about 3 gallons to top off which I do at the bulk dispenser at the T/A or Loves. I wish that GM had installed a real gauge rather than idiot messages.

[James R Moneypenny]

Originally Posted by revrusty

I just want to give a heads up to others who may be as ignorant as I have been about blue def quality. I have assumed that as long as it says 100 per cent blue def that the brand did not matter. In fact I have often filled the blue def tank at truck stops. Now my truck is in the shop because of crystals forming and stopping up the blue def system. Been a week as they took out the tank and injector and other parts. The diesel shop mechanic says that they have had tractor trailer trucks cut off while idling overnight after filling def tanks at truck stops. I had noticed the white crystals around the dispenser nozzle but didn't have the knowledge to know it was a problem. NOW I know the hard way.
Anyway. just a heads up to others like me that don't know any better. I don't know if we are allowed to mention a brand but if we can let me know and I will tell you the brand my mechanic recommends. He says they have never seen a problem when using this particular brand. Thanks for listening and hope this can help someone else avoid my problem.

Dear friend:
I had exactly the same problem with my exhaust system - put some "old" DEF in and had no idea about def crystals and contaminants. yes, I'd like to know what brands are recommended. Spent ~ $850 to replace parts/labor.
James R Moneypenny

[travelin texans]

Originally Posted by James R Moneypenny

Dear friend:
I had exactly the same problem with my exhaust system - put some "old" DEF in and had no idea about def crystals and contaminants. yes, I'd like to know what brands are recommended. Spent ~ $850 to replace parts/labor.
James R Moneypenny

Wherever you buy your DEF as long as it's marked "approved by API" it shouldn't matter if it's blue, green, polka dotted, or clear as most of it is, it shouldn't be harmful to your system.
If using DEF from truck stops I'd think it would be safe as there are hundreds of trucks daily using it & would surely hear of lawsuits out the kazoo if selling bad DEF to truckers. I'd also suspect it's tested periodically just as the fuel & the pumps are by licsensed third party technicians.

[jasin1]

Originally Posted by travelin texans

Wherever you buy your DEF as long as it's marked "approved by API" it shouldn't matter if it's blue, green, polka dotted, or clear as most of it is, it shouldn't be harmful to your system.
If using DEF from truck stops I'd think it would be safe as there are hundreds of trucks daily using it & would surely hear of lawsuits out the kazoo if selling bad DEF to truckers. I'd also suspect it's tested periodically just as the fuel & the pumps are by licsensed third party technicians.

This was at a pilot truck stop in NC, I guess this is how they bring in the def fluid? I don’t think it would be windshield washer fluid... I used the def at the pilot because I think your right... a lot of truckers use it