10 Diesel Lubricity Additives With Cetane Boost And Cp4 Protection 2026

⚡ Quick Verdict

📋 How We Evaluated

Evaluation focused on lubricity performance claims, injector cleaning capability, and fuel-system protection features. Build quality and dosing practicality were assessed via container size, measuring convenience, and treatment coverage per bottle. Value also mattered, alongside rating signals and user suitability for modern diesel systems, including HPCR scenarios.

Bottle Size	16 oz
Coverage	Treats 400 gallons
Cetane Boost Claim	Up to 7 points
Use Rate	1 oz (or 2 oz for more) per 25 gallons

What We Found

Hot Shot’s Secret Everyday Diesel Treatment (EDT) comes in a 16 oz squeeze bottle, geared toward routine refueling add-ins. The label reads like a true “everyday” multipurpose treatment, with claims that it can improve performance and maintain engine health. It highlights a cetane boost (up to 7 points) to target smoother combustion and better fuel economy. EDT also claims injector cleaning for both internal and external deposits, along with lubricity enhancement meant to help protect components like the pump and injectors. On top of that, it positions itself as rust and corrosion resistant by helping manage moisture and supporting stability against oxidation and degradation. Dosing is simple: 1 oz or 2 oz per 25 gallons.

Who It’s For

I would point EDT at drivers who want a straightforward “add it when you fuel” routine, not a specialized response to specific pump-wear fears. The squeeze format is convenient for quick handling at the pump, and it makes sense for daily drivers, light-duty trucks, and fleets that fuel often. It’s best approached as an ongoing conditioner for normal use—especially if your main goal is smoother running and fewer injector-deposit symptoms over time.

Bottle Size	40 oz
Coverage	Treats 400 gallons
Lubricity Test Claim	ASTM D6079; +43%
Cetane Booster Claim	Up to +8 points

What We Found

Archoil AR6500 is built around lubricity and modern diesel fuel-system stress. The 40 oz bottle is designed for up to 400 gallons and it’s meant to be added directly at each fill-up, with dosing guided by the long neck and measuring chamber. Where it stands out in the details provided is the ASTM D6079 reference and the claim of a 43% lubricity improvement, which directly targets wear risk in boundary-lubrication conditions. It also calls out suitability for all diesel engines, including modern HPCR systems, and explicitly references wear-sensitive parts like the CP4 pump. AR6500 further claims cetane boosting up to +8 points for smoother ignition and combustion. For deposit control, it includes a detergent package intended to remove injector deposits and help restore spray pattern performance, which can matter for economy and drivability.

Who It’s For

AR6500 is a fit for people who run variable fuel quality or drive equipment with high-pressure injection systems. I’d also shortlist it for owners who want a lubricity-and-protection outcome more than they want a “good enough” general fuel treatment. The once-per-fill routine is convenient, and the CP4/HPCR callouts make it especially relevant for anyone who’s trying to protect the wear-prone parts of the system. If your priorities are evidence-backed lubricity and pump-awareness, this is the lane it’s in.

Package Size	Two 40 oz bottles
Total Coverage	Treats 800 gallons
Lubricity Test Claim	ASTM D6079; +43%
Cetane Booster Claim	Up to +8 points

What We Found

This two-pack of Archoil AR6500 bundles two 40 oz bottles for treating up to 800 gallons total. It carries the same core theme as the single bottle: ASTM D6079 testing with a claimed 43% lubricity improvement. It also includes the same cetane booster claim of up to +8 points, aimed at smoother combustion and improved drivability. Like the single version, it’s described as suitable for all diesel engines and includes modern HPCR systems in its coverage. Injector cleaning is supported via a detergent package designed to remove deposits and help restore spray patterns. The main difference here is simply buying value and convenience—more treated volume means fewer reorder cycles.

Who It’s For

I’d recommend this set to high-mileage drivers, fleet managers, and anyone who prefers to plan refueling maintenance instead of reordering constantly. It’s also a practical option for households that run more than one diesel vehicle or piece of diesel equipment throughout the year. If the AR6500 chemistry is your preferred approach but you’d rather not buy so often, the two-pack makes that easier.

Bottle Size	1 gallon
Coverage	Treats 1280 gallons
Lubricity Increase Claim	Up to 56%
Formulation Claim	No harmful solvents or alcohol

What We Found

Hot Shot’s Secret LX4 Lubricity Extreme is positioned around lubricity protection for diesel (including USLD) and also gasoline systems. The 1 gallon size treats up to 1280 gallons, so it’s aimed at long-term, repeat dosing rather than a quick “one-and-done” fix. The standout figure in the details provided is the claim that fuel lubricity increases by up to 56%. The label also notes the formula avoids harmful solvents or alcohol, which is meant to support compatibility-minded use across diesel and gasoline tanks. Another secondary benefit it calls out is upper-cylinder lubrication, which is especially relevant for gasoline engines, but the overall positioning is still system protection through lubricity support. It’s also described as being easy to integrate alongside fuel stabilizers and other fuel system treatments.

Who It’s For

LX4 is for owners who want maximum protection over time and don’t mind buying a larger container upfront. I would shortlist it for diesel drivers who refuel over longer stretches, as well as fleets and contractors looking to reduce reorder frequency. It’s also appealing if you manage both diesel and gasoline vehicles and want one product that covers lubricity needs across fuels. What it’s less suited for is intensive injector-deposit removal as the primary goal.

Bottle Size	16 oz
Coverage	Treats 160 gallons
Lubricity Increase Claim	Up to 56%
Formulation Claim	No harmful solvents or alcohol

What We Found

The LX4 Lubricity Extreme 16 oz squeeze bottle is designed for frequent, controlled dosing with a compact container. The product details reiterate the key claim: it increases fuel lubricity by up to 56% and is meant to add lubricity back to Ultra Low Sulfur Diesel (USLD). It also repeats the no harmful solvents or alcohol formulation, which supports safer integration into normal fueling routines. LX4 positions itself around protecting fuel pumps and injectors and extends fuel system life by reducing wear and damage. A secondary benefit mentioned across fuels is upper-cylinder lubrication for gasoline, ethanol, and diesel applications, which can be useful for mixed-fuel garages. The listing also notes it’s compatible with fuel stabilizers and other fuel system treatments.

Who It’s For

I’d point this version at anyone who wants a smaller bottle option for diesel-only use (or a mixed vehicle shop) without stepping up to larger jugs. It fits moderate mileage drivers who still want regular dosing as part of routine maintenance. The squeeze format makes it easy at fill-ups, and it avoids measuring friction when you’re trying to keep things consistent. It can also be a good seasonal buy for maintenance during storage periods when lubricity protection still matters even if miles are low.

Bottle Size	1 gallon
Coverage	Treats 3200 gallons
Cetane Boost Claim	Up to 7 points
Use Rate	1 oz (or 2 oz for more) per 25 gallons

What We Found

Hot Shot’s Secret Everyday Diesel Treatment (EDT) in the 1 gallon size is scaled for heavier usage and treats up to 3200 gallons. It keeps the same multipurpose concept as the smaller bottle: everyday performance maintenance in one treatment. The label highlights a cetane boost up to 7 points, which is aimed at smoother combustion and better fuel economy. EDT also includes injector cleaner performance for internal and external injector deposits, which is meant to support restoration of spray quality. For protection, it includes lubricity enhancement to safeguard pump and injector components, plus rust and corrosion prevention through moisture demulsification and stability against oxidation and degradation. Dosing stays straightforward: 1 oz or 2 oz per 25 gallons.

Who It’s For

This version fits high-mileage drivers and operators who want consistent dosing without repeatedly purchasing small bottles. It’s a good match for contractors, fleet managers, and anyone who fuels frequently and values routine injector and system upkeep. The big capacity can also help keep the treatment cost per gallon down in practice—assuming your pricing aligns with typical refill patterns. I’d position it for owners who want overall maintenance and mild performance improvements rather than targeted CP4-style risk mitigation.

Bottle Size	32 oz
Coverage	Treats 320 gallons
Lubricity Increase Claim	Up to 56%
Formulation Claim	No harmful solvents or alcohol

What We Found

Hot Shot’s Secret LX4 Lubricity Extreme 32 oz focuses more on lubricity and fuel-system protection than on injector cleaning. It claims to increase fuel lubricity by up to 56%, with an added emphasis on restoring lubricity back to Ultra Low Sulfur Diesel (USLD). The formulation is positioned as free of harmful solvents or alcohol, which supports compatibility-minded use and reduces the risk of unwanted chemical effects. The product also claims to extend fuel system life by protecting pumps and injectors from wear and damage. It additionally includes upper-cylinder lubrication that’s described as working across gasoline, ethanol, and diesel—useful if you run mixed fleets. Like other sizes, it’s framed as compatible with fuel stabilizers and other treatments.

Who It’s For

LX4 32 oz suits drivers who want a mid-size option between a small squeeze bottle and a bulk jug. It’s aimed at moderate-to-high mileage diesel owners who prefer fewer reorder events. The USLD lubricity restoration angle is especially relevant for vehicles that regularly see commodity diesel. If your goal is component-life protection and wear reduction more than cetane jumps or deposit-focused injector cleaning, this is the right direction.

Package	Pack of 2
Bottle Size	16 oz each
Lubricating Content Claim	Five times more lubricating content than other Stanadyne additives
Fuel Compatibility	Ultra-low sulfur diesel; bio up to B20

What We Found

Stanadyne Lubricity Formula is designed to add lubricity and reduce wear in diesel fuel systems. The pint bottle pack of two leans into both cleaning and protection with a multi-function claim set. The provided details state that it delivers five times more lubricating content than other Stanadyne additives, which suggests a more aggressive wear-focused intent. It also claims injector and fuel system cleaning, plus demulsification of water to help improve filter or separator efficiency. Corrosion and rust resistance are presented as explicit benefits, with an emphasis on keeping fuel fresher. It’s described as formulated for ultra-low sulfur diesel and usable with biodiesel up to B20, which makes it relevant for blended fuel situations.

Who It’s For

I’d shortlist Stanadyne when you suspect wear may already be happening or when your routes involve higher water risk. It’s also a fit for biodiesel users up to B20 who still want lubricity support that tolerates blend conditions. The two-pack format helps keep dosing consistent across seasons without constant re-shopping. Overall, I’d look at this when lubricity and water management matter more than cetane boosting or DPF-specific deposit control.

Bottle Size	64 oz
Coverage	Not provided in the provided details
OEM Approval	Approved by Original Equipment Manufacturers (OEMs)
Lubricating Content Claim	Five times more lubricating content

What We Found

Stanadyne 38561 Diesel Lubricity Formula comes in a 64 oz bottle and is geared toward diesel-only lubricity enhancement. The label notes approval by Original Equipment Manufacturers (OEMs), which is a confidence signal for compatibility. The product also repeats Stanadyne’s key differentiator: five times more lubricating content than other Stanadyne additives. The features described here emphasize wear reduction, with water demulsification intended to support filter or separator efficiency. For this specific size, the included details don’t fully list injector cleaning or full corrosion wording, but the overall positioning matches Stanadyne’s typical role as a lubricity-and-protection focused formula. That OEM approval mention is valuable if you prefer a conservative, manufacturer-aligned approach.

Who It’s For

This is a good fit for owners who want OEM-aligned lubricity protection and prefer a diesel-focused formula. It works well for older fleets and steady day-to-day use where equipment compatibility is the priority. If you’re in areas or routes where water contamination is more likely, demulsification support is worth considering. I’d also see it as a choice for drivers who don’t want to chase cetane or drivability changes—just maintain fuel-system health through lubrication and water handling.

Package Size	Case of 12 bottles
Bottle Size	16 oz each
Coverage per Bottle	Treats 125 gallons
Bio Compatibility	Can be used with bio diesel up to B20

What We Found

Stanadyne Lubricity Formula in a case of 12 bottles is designed for high-volume users who need consistent lubricity dosing. The provided details emphasize five times more lubricating content than other Stanadyne additives, framing it as wear-focused when excessive wear is a concern. This case listing also includes clear coverage math: each 16 oz bottle treats 125 gallons, which makes budgeting straightforward. The product claims to clean and protect injectors and all fuel system components, and it also demulsifies water to help support filter or separator efficiency. It further targets corrosion and rust formation while helping keep fuel fresher. The details also mention compatibility with ultra-low sulfur diesel and biodiesel blends up to B20, which matters for blended-fuel operations.

Who It’s For

This case option fits fleets, maintenance shops, and contractors managing multiple diesel units who want predictable costs. It’s also practical for biodiesel-ready operations using blends up to B20 and needing lubricity consistency across tank cycles. Since the bottle treatment volume is spelled out, inventory planning is easier when you’re buying in bulk. I’d choose this when lubricity, corrosion control, and water management are more important than cetane or HPCR-specific deposit-control features.

What to Look For Before Buying

When I’m shopping for the best lubricity additive for diesel fuel, I start with the failure I’m trying to prevent—wear first, then everything else. Look for lubricity improvement as the core feature, then confirm injector cleaning and water/corrosion handling if that matches your real-world fuel conditions. I also pay attention to dosing simplicity, because an additive only helps if it actually gets used consistently. Finally, I compare coverage (treats per bottle) so I can estimate cost per treated gallon instead of guessing based on container size alone.

Check Prioritize lubricity evidence and wear protection

Look for references to a standard lubricity test or at least a quantified lubricity improvement claim. If the vehicle uses HPCR systems, search for messaging that explicitly references wear-sensitive components like CP4. Higher lubricity performance matters most for pump and injector longevity. Choose an additive that matches the specific risk level rather than only chasing general “fuel treatment” wording.

Value Compare real cost per treated gallon

Use the stated “treats X gallons” to calculate cost per treated gallon. Bulk sizes often reduce per-gallon cost, but only if the bottle can be used within a reasonable time. Multi-pack options can help if multiple vehicles or high mileage justify the upfront spend. Coverage clarity in the label is a useful signal for easier budgeting.

Rating Use rating signals, but read the dosing fit

Amazon rating data helps with adoption and consistency, but it cannot replace suitability checks. Confirm the additive’s recommended dose aligns with refueling habits and tank size. Products marketed for “everyday use” should still support your maintenance goals. A mismatch between dosing frequency and usage patterns leads to inconsistent protection.

Verify Verify compatibility with your fuel and emissions setup

For biodiesel blends, verify the allowable blend limit, such as B20 compatibility where stated. If diesel equipment uses sensitive emission components, look for deposit-control claims that match those needs. For USLD-heavy regions, prioritize lubricity restoration wording. When in doubt, confirm compatibility with manufacturer guidance and avoid stacking conflicting treatments.

Frequently Asked Questions

What should matter most when choosing a lubricity additive for diesel fuel?

Lubricity improvement should be the first filter, since it’s directly tied to reducing wear in pumps and injectors. Next, I would look for injector cleaning support if you already notice symptoms like rough running or reduced fuel economy. Third, water and corrosion handling matter a lot when fuel quality varies. The dosing routine should also be realistic, because consistency is what makes the protection meaningful.

Do lubricity additives also improve fuel economy and drivability?

They can, but the “why” depends on the product. When lubricity improves, friction and wear can drop over time, which supports smoother operation. Cetane boosters can make combustion easier and often feel more immediate through smoother ignition. Injector cleaning can help restore atomization and efficiency too, which can translate into better economy and drivability.

Can lubricity additives be used with biodiesel blends?

Some formulas do—when the listing specifies a blend limit, like B20 compatibility. Always follow the labeled maximum and the recommended dosing rate. If you use blended fuels, pay extra attention to the additive’s water demulsification and corrosion control claims, since storage and fuel chemistry can change seasonally.

How often should a diesel lubricity additive be used?

Many additives are designed for use at every fill-up for routine wear protection. Follow the label dose so you don’t under-treat or overload the tank. Some products may suggest step-up dosing for poor fuel conditions—so it’s worth reading the guidance rather than assuming every tank needs the same amount. In most cases, consistent dosing across tanks is what delivers the best results.

Is injector cleaning a must-have feature in a lubricity additive?

Not always, but it becomes important if you’re seeing symptoms that commonly come from deposits—like rough idle, hard starts, or noticeably worse fuel economy. If injector deposits are your suspected issue, I’d pick a product that explicitly targets cleaning and spray pattern restoration. Lubricity-only treatments can still help with wear, but they may not address combustion inefficiencies caused by dirty injectors.

🎯 Final Verdict

For diesel owners who care most about wear protection in modern high-pressure systems, I’d choose Archoil AR6500 as the top pick. It pairs ASTM D6079 lubricity testing with a 43% improvement claim and it explicitly targets CP4 and HPCR risk. Hot Shot’s Secret Everyday Diesel Treatment (EDT) is a solid alternative when you want straightforward everyday cleaning plus cetane boosting up to 7 points and a simple routine dose. I’d buy AR6500 when wear-focused lubricity evidence matters most, then decide between the rest based on your fuel volume and how convenient the dosing schedule is for your fueling habits.