Rislone 4784 DEF Crystal Clean™ Diesel DEF & SCR Emissions System Cleaner, 11.8 oz

We have a 2016 Ram 1500 Ecodiesel and prior to using this product I was eating up half a tank of DEF every month. I ran back to back bottles and started using the DEF at our local Fry’s store. The DEF consumption went down dramatically. Folks, this stuff really works. We are having to fill the DEF every two months now. Fantastic product and works extremely well.

I bought a used 2021 F250 with 75k miles. At first it was drinking DEF. I used 3/4 of a tank on a 900 mile road trip. I used this product on the first tank on my 5900 mile move to Alaska from Virginia. The first 3/4 tank of DEF, with the product in it, got me to Indianapolis, about 800 miles. The second tank I started using the Rislone DEF Treatment in every box I put in the truck, it got me to Mitchell, SD which was about 1000 miles and I used half a tank. About 1200 miles later I put 1 box of DEF in before I crossed into Canada, and stocked up on 3 boxes knowing I had about 3k more to go. Keep in mind, I'm hauling a 20ft enclosed trailer full of all my earthly possessions, and I have quite a few tools and heavy things. Something happened after that first 3k miles. I made it the next 3k miles and only used 1/2 tank. Now when I fill up it says 7500 miles to empty. I don't know if that's true, but it's been a long time since I've had to buy DEF.

It works wonders, clean my tank and nozzle!

I used this in DEF tank since I had been geting P20EE codes regularly. I could see crystalization around pour tube, cap, etc. I put this in, then I got the dreaded Poor DEF Quality message and P20EE code again. Then it went away. A few miles later, back again. Then after a few days. maybe 75-80 miles, no more codes. Took a long trip of 650 miles, plus local driving, code and DEF message have never appeared again. Seems to do the trick. I also add in the Rislone maintenance DEF fluid product. Seems to all be working as intended.

As always, I'm skeptical when it comes to product performance—but this one? Amazing. I never owned a diesel until I bought my '21 GMC HD2500 Duramax. I love it, but man, diesel engines demand preventive maintenance. You can't wait for things to break—you’ve got to stay ahead of it with products that help reduce or even prevent issues. This particular product is excellent. Since the day I bought my truck, I’ve had nonstop problems with the DEF tank sensors sticking. Sometimes it would show full when I knew it wasn’t, and other times it claimed to be half empty right after a fresh fill-up. Totally unreliable. And what did the dealer say? “It’s inadvertent.” That word should be banned—it’s just an excuse to ignore a real problem. Let me tell you—this product works. Period. And it worked fast, too. Absolutely amazing.

Very good idea and quality.

Use this in my 2023 Silverado 3 liter diesel To fix a bad crystallization problem with crystals, forming all over the def tank sender Took about a 4 days to work on mine But haven’t had any problems since using it

My 2018 gmc terrain diesel kept popping up telling me that the exhaust fluid is poor and that after 99 miles my vehicle will not go over 65mph. But every time it came up it said the same thing, it always said 99 miles. I use the premium DeF and I’m not sure how there was an issue. I purchased this product because it says it clears the fluid, also said it could take days of driving before the product fixes the issue. I’m a daily driver and spend a lot of time I town and on the freeway, I’m going on 2 weeks and still the warming comes up sporadically. It still says I’ve got 99 miles, I guess ima have to find somewhere or someone to flush the Def system, sucks cause I really hoped this DEF crystal clean additive would do as it advertises. :(