DEF ( truck stop vs. store purchased)

[p024576kos]

Is it ok to use and mix store purchased DEF with truck stop DEF that has been solely used for last 3 years?
Any recommended DEF brand to use or avoid?
Thanks

[oldenavy]

As long as it complies with the API standard and isn’t past it’s date, it should be fine. I mostly used jugs from stores in 3 pickup trucks with zero problems. I never pay attention to the brand. Name brand just cost more.

Old DEF that has been stored in high temperatures can go bad. I always buy from stores that have stock turnover like Walmart or other big box stores.

[KenZ71]

My preference is from the pump while I am getting fuel. However with my DEF fill at passenger rear and fuel up front it is a huge pain.

So I tend to keep a jug or box and refill at the pump then pour into tank.

Walmart branded jugs if sealed work just fine. Too often the seal is not intact though so no guarantee it is def vs water or who knows.

[thegats1]

Brand doesn't matter. I agree with KenZ71. Because it looks like water, there are some wonderful fellow Americans that like to buy it, use it, refill it with water, and return it and get their money back. I've never used the DEF pumps at truck stops, but I may when we start taking multiple long winded trips (after retirement). I often just buy the Loves branded stuff at the truck stop, but it is a bit pricey. Usually because I didn't plan ahead.

[2cyber71]

I have only bought my DEF at truck stops since 2020 when I got a DEF diesel.
TA, Loves.
If you have a Sam's Credit Card you get 5% back
It thinks you bought gas.
So $4 becomes $3.80 a gallon.
My DEF doesn’t sit too long, I have 47,000 miles on my motorhome since April 2020

[bneumann]

Found that they are much cheaper at Freightliner or other service centers, than at Walmart or other retail places ... & most likely less tampering probability ... always check seals.

[Homeby5]

Wow...never thought about buying water instead of DEF? Learned something new.

[DRM901]

You should test the DEF with a Refractometer before you put it on the tank. Especially if you have a newer diesel that tests for quality. Only $22 for piece of mind.

[spock12]

Originally Posted by DRM901

You should test the DEF with a Refractometer before you put it on the tank. Especially if you have a newer diesel that tests for quality. Only $22 for piece of mind.

Thanks a bunch, I’ll order one from Amazon. I had never given it much thought about someone tampering with the def at Walmart. I havebought jugs at Walmart without seals. I’ll buy from truckstops from now on. From now on I’ll check the seals. I’ll buy a couple of jugs and refill them at truckstops. I guess you are never to old to learn new things

[RCC]

I prefer the DEF from truck stop pumps over jugged DEF for two reasons: it's cheaper (about half the price) and it's probably fresher. But pumping bulk DEF directly into my DEF tank is inconvenient since my diesel fill port is near my left front axle and my DEF fill port is near my right rear axle. So here's how I do it: I keep two empty DEF jugs in my basement. After I've filled my diesel tank, I also fill the two DEF jugs while I'm still at the pump. I store the two filled DEF jugs back in my basement, then use them to fill my DEF tank that evening at the camp ground. This procedure saves me money, ensures me I'm getting fresh, unadulterated DEF, and it only take me two more minutes at the pump so I'm not holding up the trucker behind me in the line.

[Dutch Star Don]

It doesn't matter to me where I get my DEF, other than convenience. During the height of the DEF head issues, I started keeping my DEF tank full. Consequently, when we get fuel, I rarely need more than a couple gallons of DEF. I'm not going to start the coach and pull it forward to add 2-3 gallons of DEF.

For me, paying a few dollars more the store DEF is worth the convenience of filling at my leisure. Most of our trips are around 1000 miles or less, so I fill the DEF when I get home.

We're currently prepping for a month-long trip of several thousand miles. I'll keep an empty DEF jug in a bay and fill it if it's convenient while I'm getting fuel.

The only downside of adding DEF by the jug....for an old guy with a bad back and knees....is standing there and holding the jug. I made/added this shelf to the back side of my DEF bay door. I place the jug on the shelf and wait for it to empty.

[NevadaNick]

Over 500,000 mi in pickups, suv and 2 motorhomes and never had bad def. My 2011 GMC flashed poor quality def twice in the time i had it and it was not the def itself but sensors that were bad. Majority of the def i bought at Walmart.

[edgewant]

Originally Posted by RCC

I prefer the DEF from truck stop pumps over jugged DEF for two reasons: it's cheaper (about half the price) and it's probably fresher. But pumping bulk DEF directly into my DEF tank is inconvenient since my diesel fill port is near my left front axle and my DEF fill port is near my right rear axle. So here's how I do it: I keep two empty DEF jugs in my basement. After I've filled my diesel tank, I also fill the two DEF jugs while I'm still at the pump. I store the two filled DEF jugs back in my basement, then use them to fill my DEF tank that evening at the camp ground. This procedure saves me money, ensures me I'm getting fresh, unadulterated DEF, and it only take me two more minutes at the pump so I'm not holding up the trucker behind me in the line.

X2.

[DRM901]

Originally Posted by spock12

Thanks a bunch, I’ll order one from Amazon. I had never given it much thought about someone tampering with the def at Walmart. I havebought jugs at Walmart without seals. I’ll buy from truckstops from now on. From now on I’ll check the seals. I’ll buy a couple of jugs and refill them at truckstops. I guess you are never to old to learn new things

I get all my DEF at Walmart, but I check every seal before I buy it. I don't refuel at a lot of truck stops. I find better prices at regular gas stations using GasBuddy, even using open roads/TSD card. Plus, I like having 5 gal in the basement for when we are in remote areas.