Summer means long days, heavy loads, and hard-earned miles—on the job or off the grid. Howes Diesel Defender is built for diesel pickups that work and play above 32°F. It cleans injectors, boosts lubricity, removes water, and improves fuel economy. Use it at every fill-up to keep your truck running strong all summer.
Comes in 15 oz, 1 quart, and half-gallon bottles—convenient sizes to match your diesel needs, whether you’re running a single pickup, managing a fleet, or fueling equipment on the job. No matter the size of your tank, Diesel Defender makes it easy to get the right dose every time.
Part # | Size | Treat Rate |
---|---|---|
103024 | 15 oz. | 1 oz. to 5 gal. |
103022 | 1 quart | 1 quart to 160 gal. |
103020 | 1/2 gal. | 1/2 gal to 320 gal. |
I've been using Howes Diesel Defender in my diesel truck for a month, and I'm already seeing positive results. While it's still early days, I'm encouraged by the initial improvements in fuel economy and overall engine performance. So far, I've noticed: Improved Fuel Efficiency: My truck seems to be getting better mileage, which is a great start. Smoother Engine Operation: The engine feels a bit quieter and runs more smoothly. I'm excited to continue using Diesel Defender and see if these positive trends continue over time.
-M. LUHRS
Delivers unmatched lubricity—more than any other Howes product or leading competitor
Reduces internal wear to protect your engine over the long haul
Ideal for diesel pickup trucks needing daily power and protection
Lab-tested using ASTM D975 HFRR wear scar test
Outperforms both U.S. and European lubricity standards
Supports long-term engine health and peak performance
Powers through tough deposits with advanced IDX4® Detergent
Cleans your entire fuel system in just three treatments (when used as directed)
Restores lost power by removing harmful carbon buildup
Prevents new deposits from forming for long-term performance
Keeps your diesel pickup running strong—whether you’re hauling heavy or cruising the open road
Maximizes every gallon—formulated to improve fuel economy by 5% or more
Removes water safely to protect your fuel system and engine
Keeps injectors clean for a consistent, efficient spray pattern
Prevents wasted fuel and helps maintain peak combustion
Use at every fill-up to save money and keep your pickup running strong
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