Best Diesel Additives of 2025

"I've been using Hot Shot's Secret Everyday Diesel Treatment in my Ford F250, and I couldn't be happier with the results! This treatment has made a noticeable difference in the performance of my truck. It helps improve fuel efficiency, reduces engine noise, and keeps the fuel system clean. My truck runs smoother, and I've noticed a slight improvement in acceleration. The 16-ounce squeeze bottle is super convenient and easy to use—just squeeze the right amount into the tank, and you're good to go. Overall, this is a must-have for any Ford F250 owner."

"After purchasing our 2012 VW TDI diesel at 140K miles, I started researching best practices to keep these little engines happy. I can't comment on the comparative difference as I ran this from almost day one. What I like is the claimed increased lubricity and cetane boost that is supposed to bring our crappy D2 up to reasonable levels. The Hot Shot's EDT seems more concentrated and affordable than the competition. It's a negligible cost for a fill-up, and I hope they keep it that way."

"I have a Cummins engine in my truck. With regular use, I've noted a considerable improvement in mileage after using this product. It helps me get a couple of extra mpg when I use this. Money well spent!"

"I discovered this oil after my dealership recommended it for my truck. It's absolutely worth the price to keep the engine running smoothly. I add it during every gas refill, and I've noticed a significant reduction in noise levels and improved durability. I wouldn't consider driving my truck without it."

"After using this product in my 2001 7.3, it really brought my truck to life! The performance is incredible, and I've experienced better fuel mileage and easier starts. I've shared my success with everyone I know!"

"During a month-long road trip in my Sprinter with a 3.0 V6 Turbo, I noticed my mileage increased by 0.9 mpg, and the engine runs much smoother than before. I'm quite satisfied with the results so far!"

"I noticed an immediate difference in performance the first day I used it. After adding 8 oz per 20 gallons on low fuel and topping off, the mixture worked wonders. My throttle response improved dramatically, and I gained 3+ mpg in town. Plus, my truck starts quietly and runs super smooth!"

"After using Hot Shot Secret, my fuel economy jumped from 16 to over 20 mpg. Driving my 2005 Chevrolet Duramax, I was amazed at the performance, especially scaling the high passes on I-5. With 200,000 miles, my injectors remain clean, and the cetane boost is fantastic!"

"I found my RAM ecoDiesel was sensitive to diesel quality. After using a different supplier, the engine struggled until I used this clean and boost product. It restored my engine's performance and helped reduce the particulates in the exhaust. Now, I’m careful about diesel quality and use this product regularly to keep everything clean!"

“I’ve been using this product for many years on both of my Cummins diesels. I’ve never had to replace a lift pump or an injector, and my rigs have plenty of power. I will continue using this product.”

“Stanadyne is my go-to for all my diesel engines, including Duramax and Detroit. I’ve experienced no problems or issues at all.”

“After about 600 miles, my motorhome feels smoother, and while I can't measure the difference precisely, my gut tells me to keep buying it.”

"I was in northern Wisconsin in January 2018, and my fuel froze. I had to get towed to warm up my truck, which was a couple hundred bucks I was not happy spending. A truck place recommended this product to me, and I’ve been using it every winter since. It works great."

"I like using this product and ordering from them. It gets here pretty quick."

"This fuel supplement is a must for all diesel engines in weather below 30 degrees to prevent diesel fuel from jelling. It's a very expensive and time-consuming issue to fix. I use the 'white' additive all winter and switch to the 'grey' additive the rest of the year. The product arrived on time at my home. I would buy from this supplier again."

"I noticed my fuel economy dropped by 2.5 - 3 mpg, but after using this product, my mpg is back up, even 0.3 mpg better than before. My truck feels amazing!"

"Since I started using this product, my motor runs smoother and quieter. I’m impressed with the improvement in mileage too. Good stuff!"

"I just started using it and haven’t seen mileage improvements yet, but I'm hopeful it will help after continued use. My intake upgrade helped, but I'm eager to see the results from this."

"I started using this for my 2020 Ford 6.7 diesel and have had no issues even in temperatures down to -2 degrees. It’s been great for measuring with a ketchup dispenser we bought, making it easy to pour. I definitely recommend buying it by the gallons for the winter."

"After switching from Howes Anti Gel to this product for my 2016 Chevrolet Duramax, I can say the jug is super easy to use and doesn’t leak. I use it every time I fill up to keep my fuel clean and lubricated, which is crucial for maintaining my CP4 fuel system."

"I can't say enough good things about this product. My 2007 LBZ Duramax runs amazingly with it, and I notice a significant difference when I don’t use it. The steering wheel vibrates more and I see more black smoke without it. It’s a bit pricey, but definitely worth it!"

"I add this to every tankful of diesel. It's a fantastic top-end lubricant and injector cleaner. My truck runs smoothly with minimal smoke. Since my engine is deleted and tuned, I closely monitor all engine parameters, and this product keeps everything in check."

"This product works just as advertised. I've been using Howes products for years, and my diesel really needs this. I highly recommend it!"

"I was impressed when I tried this during a recent cold snap. There was no gelling, and my truck started right up. I plan to use this when traveling instead of plugging in the block heater."

"I drive a 2016 Ram 3500 with the Aisin transmission and have always used a fuel additive. After switching to Stanadyne, I noticed an average fuel mileage of 17.7 to 18.0 MPG on the highway, and I even reached 19.2 MPG on a recent trip. I'm maintaining my truck well and appreciate the preventative maintenance aspect."

"For years, I've relied on Stanadyne in my tractor and never faced any fuel issues. After the freeze of 2021, I realized that the previous Ford Performance Enhancer didn't prevent icing, but Stanadyne does everything I need—it's economical and keeps my engine running smoothly."

"I've used Stanadyne in my 06 LBZ for years. Every time I fill up, I add it, and it keeps my injectors clean and the engine performing optimally. I haven't had any problems, so I consider it inexpensive insurance for my diesel engine."

"I was a skeptic about products claiming performance and MPG improvements. However, after using this in my 2014 RAM 2500 with a Cummins 6.7L engine, I saw my MPG increase from 16.3 to 17.6 while driving the same daily route. The truck feels smoother and has more pep, and I’m now convinced of its benefits!"

"Having used this product for several years, I've found it to be excellent, especially in extremely cold weather — I’ve never had a problem with fuel gelling. I use two bottles on the first fill-up and then one for every subsequent fill-up."

"This product was exactly what I needed! Using one bottle per fill-up means no more measuring or refilling, which is super convenient. After using it since my truck was new, I recently checked the fuel filters and found no signs of water. I’m averaging 17 MPG city and 20 MPG highway, while my friend, who doesn't use any additives, is only getting 14.3 MPG."