10 Best Gas Additives for High Mileage Cars [2025]
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Finding the best gas additives for high mileage cars can significantly enhance performance and fuel efficiency. These products are designed to clean fuel systems, reduce engine wear, and improve overall engine health. In this article, we will explore the top 10 gas additives currently available, helping you make an informed choice for your vehicle.
Top 10 Gas Additives for High Mileage Cars in the Market
Best Gas Additives for High Mileage Cars Review
SaleBestseller No. 1
Lucas Oil 10977 High Mileage Fuel Treatment - 5.25 Ounce
- Clean fuel injectors and keeps them clean
- Reduces intake valve deposits and combustion chamber deposits
- Lubricates critical components in the fuel system and engine
- Stops knocking and hesitation
- Lessens oil contamination in older engines
SaleBestseller No. 2
STP High Mileage Fuel Injector Cleaner and Carburetor Cleaner Treatment, Bottled...
- Fights deposit buildup and engine friction
- Maintains optimal engine efficiency
- Safe for any gasoline engines
- Compatible with cap-less gas systems
- 1 bottle treats up to 21 gallons of gasoline
SaleBestseller No. 3
Chevron Techron High Mileage Fuel System Cleaner, 12 oz, Pack of 1
- Restore power and performance - Restores lost power and performance by removing gum, varnish, and other fuel system deposits.
- Maximize fuel economy - Keeps engines clean, and protects from deposits that rob engine efficiency and reduce fuel economy.
- Protect the fuel system and fuel gauge sensor from various types of corrosion - Multiple corrosion inhibitors protect metal components (both ferrous components like iron and steel, and non-ferrous components like copper and silver) from the damaging effects of corrosion.
- Vehicles with higher mileage accumulation can suffer from the effects of age - including carbon build-up and corrosion in the fuel system. Techron High Mileage Fuel System Cleaner helps keep your engine humming, no matter how many roads your vehicle has traveled.
- Techron High Mileage Fuel System Cleaner is fully compatible and protective in all commercially available ethanol blends (E10, E85, etc).
Bestseller No. 4
Bar's Leaks 1000 High Mileage Engine Repair, 16.9 oz | Restores Performance,...
- RESTORES PERFORMANCE: Contains a combination of the best performance additives to repair the most common oil-related problems
- INCREASES COMPRESSION AND HORSEPOWER: Restores lost compression and power, reduces noise and oil consumption, while improving the performance of worn cylinders, rings, bearings, and seals
- STOPS LEAKS, NOISE, AND SMOKING: For most vehicles, this is your last chance before paying an expensive repair bill or replacing the vehicle
- FRICTION MODIFIERS: Engine Repair can be used to top off the existing oil when low, or add a bottle when changing the oil and filter
- REPAIR-IT: Engine Repair-It can be used to top off existing oil when low or add a bottle when changing oil.
Bestseller No. 5
STP High Mileage Oil Treatment + Stop Leak - 15 FL OZ
- Protect the engine in your high-mileage vehicle with STP High Mileage Oil Treatment + Stop Leak. Formulated especially for vehicles with over 75,000 miles, this high-viscosity engine additive includes ZDDP oil additive as an anti-wear agent for protection. This STP oil treatment creates a thick cushion between moving engine parts to help fight metal-to-metal friction. Engine stop leak helps to rejuvenate seals and gaskets and stop engine leaks, noise and smoking to improve performance. Add to engine oil with each oil change during car maintenance. It's suitable for cars, light trucks and SUVs.
- One 15 fl oz bottle of STP High Mileage Oil Treatment + Stop Leak
- ZDDP oil additive prevents wear to protect your high-mileage vehicle
- High-viscosity formula creates a thick cushion between moving engine parts to reduce friction
- Leak stopper helps prevent engine leaks, noises and smoking and helps to rejuvenate seals and gaskets
Bestseller No. 6
Lucas Oil 10118 High Mileage Oil Stabilizer - 1 Quart
- Excellent at fighting off sludge
- Lubricates all internal parts to minimize wear in any engine
- Raises oil pressure
- Eliminates the noise, emissions and oil consumption associated with worn engine
Bestseller No. 7
Gumout 510023 Regane High Mileage Fuel System Cleaner, 6 oz. (Pack of 6)...
- The ALL NEW CarbonClear technology combines the PEA cleaning power you have come to trust with PIBA, and a patented technology for a better clean. The combination of the 3 detergents work synergistically to provide better cleaning power (new formula) vs. just PEA alone (old formula).
- Conditions upper cylinder to reduce friction and wear in high mileage vehicles
- Fights ethanol and water corrosion and prevents future carbon build-up
- Provides maximized performance and fuel economy in one fill-up
- Will not void OEM/manufacturer's
Bestseller No. 8
High Mileage Motor Treatment – Gas & Oil Additive for Fuel Injectors, Oil...
- 🧽 Cleans Fuel System – Removes deposits from fuel injectors and carburetor jets to restore smooth performance.
- 🛢️ Reduces Oil Burning – Added to crankcase oil, it helps dissolve sludge and varnish that contribute to oil consumption in older engines.
- 🔧 Lubricates Upper Engine Parts – Protects valves, cylinders, and other critical components to reduce wear over time.
- 🚗 Improves Engine Longevity – Use regularly to maintain smooth operation and reduce long-term wear in high-mileage engines.
- ✅ Safe & Compatible – Works in all gasoline fuels and motor oils — conventional or synthetic.
Bestseller No. 9
BestLine Racing Diamond Nano-Lubricant Engine Oil Additive For Gas & Diesel...
- Reduces friction by approximately 60% compared to conventional engines, by forming an ultra-low friction film on top of the Diamond Nano-coating. Oil additive for car engine, and oil treatment for car and truck engines.
- Use for any type of vehicle, gasoline and diesel engines. Use in motorcycles, cars, classic cars, race cars, commercial trucks, and everything in between.
- More Concentrated High-Pressure Diamond Nano Engine Treatment Formula. Helps to reduce oil changes and engine noise. Returns power and life to high mileage vehicles. Superior Heat Resistance maintains lubrication integrity up to 1,800°F (982°C), outperforming conventional PTFE-based additives. Universal Compatibility is effective in gasoline, diesel, hybrid, and racing engines across all platforms.
- Use one bottle for every 5 quarts of oil; it is best if used at every oil change. Dual-Action Formula combines cleaning detergents with protective additives to: Remove existing sludge, Prevent new deposit formation, and neutralizes acidic oil breakdown. Restore your engine easily with BestLine Racing Diamond Nano Lube, a metal surface treatment.
- Extreme Heat Resistance and Boundary Layer Protection and Surface Polishing & Friction Reduction The nanoparticles (5-10nm size) act like microscopic ball bearings between moving parts. That fills microscopic grooves in cylinder walls and bearing surfaces, polishes metal surfaces to mirror-like smoothness through mechanical action, and reduces friction by up to 60% compared to conventional oils.
Bestseller No. 10
XADO EX120 Motor Oil Additive - Engine Restore - Ceramic-Metal Coating and...
- Rebuilds and Protects Engine Parts for 60,000 Miles: This advanced engine treatment rebuilds worn metal surfaces and forms a protective metal-ceramic coating, significantly extending the lifespan of your engine components and providing durable protection against future wear for up to 62,000 miles.
- Significant Fuel Efficiency Improvement: Reduces fuel consumption when the engine is idling and during normal driving conditions. This efficiency boost not only saves money on fuel but also reduces your vehicle's environmental footprint.
- Restores and Optimizes Oil Pressure: This treatment helps increase the oil pressure in your engine to its optimal nominal value, ensuring that all engine parts are well-lubricated. This leads to reduced friction and wear, promoting smoother engine operation and longevity.
- Enhances Engine Performance and Acceleration: By leveling and increasing compression in the cylinders, this treatment increases overall engine power and improves acceleration. You'll notice a more responsive and powerful performance, making your driving experience more enjoyable and dynamic.
- Simple Three-Stage Treatment Process: Designed for vehicles with an oil capacity of up to 10 quarts, this treatment requires just 3 syringes for a complete application. Follow the straightforward three-stage process: warm up the engine, apply the treatment, and repeat after specific mileage intervals to achieve optimal results.
Key Takeaway
Choosing the right gas additive is essential for maintaining high mileage cars and ensuring optimal performance. The best gas additives for high mileage cars can help extend engine life and improve fuel economy. By considering the options presented, you can select a product that meets your car’s specific needs and keeps it running smoothly.
