Best Cummins Turbocharger Upgrades for 2026: Top ATS Diesel, BD Diesel Picks

The best Cummins turbocharger upgrade depends on the generation under the hood and the power level the build targets. The 5.9L Common Rail (2003-2007) and the 12-valve and 24-valve mechanical platforms respond exceptionally well to single and compound turbo upgrades. The 6.7L (2007.5-2019) benefits from a performance manifold package that frees up exhaust flow and pairs with an upgraded single turbo to move the power curve without the complexity of a full compound conversion. ATS Diesel and BD Diesel build the most trusted kits for these platforms in 2026 -- kits engineered to fit correctly, spool predictably, and hold up under sustained towing and street use.

This guide covers the best Cummins turbocharger options for the 5.9L and 6.7L platforms, how to match the kit to the build, and what the engine tells you when the stock turbo is past its service life.

Cummins Turbo Sizing by Generation

The right turbo size for a Cummins build is determined by target power level, injector sizing, and how the truck is used. A turbo that is too large for the injectors and tune produces poor low-RPM spool and excess smoke. A turbo that is too small for the build limits top-end power and elevates EGTs under load.

5.9L Common Rail (2003-2007): The 5.9L runs a single variable geometry HY35 or HE351VE turbocharger from the factory. These units are capable but sized conservatively for stock power levels. The most popular upgrade path on the 5.9L is a compound turbo kit -- a larger primary (atmosphere) turbo that pre-charges a smaller secondary (high-pressure) turbo, producing strong spool at low RPM with maximum airflow at the top end. ATS Diesel's Aurora compound kits are the benchmark for this platform, available in multiple sizes to match the injector and tune level.

Early 5.9L (1994-1998): The P-pump 5.9L benefits from the same compound approach at lower power tiers. The ATS Aurora 3000/5000 compound kit is the starting point for early 5.9L builds, sized appropriately for the injection pump's fuel capacity on a stage 2-3 tune.

6.7L Cummins (2007.5-2019): The 6.7L uses a larger variable geometry turbo from the factory. Performance gains on the 6.7L come from a combination of a quality exhaust manifold and a matching upgraded single turbo. BD Diesel's Screamer turbo manifold package eliminates the restrictive factory exhaust manifold and pairs it with a larger performance turbo, improving both peak power and throttle response.

Top Picks for Cummins Turbocharger Upgrades

For the 6.7L Cummins (2013-2018), the BD Diesel 6.7L Screamer Turbo Manifold Package (1045871) is the leading street and tow upgrade. BD Diesel pairs an upgraded turbocharger with a matching cast exhaust manifold to free up exhaust flow that the factory system restricts. The result is improved spool time, stronger mid-range torque, and better top-end power on a tuned 6.7L without the complexity of a compound conversion. This is the most complete bolt-on turbo upgrade available for the 2013-2018 6.7L.

For the 5.9L Common Rail (2003-2007), ATS Diesel builds two compound kit tiers. The ATS Aurora Plus 5000 Compound Kit (202-A52-2272) is the most popular option for a street and tow 5.9L running 200-250-over injectors and a stage 2-3 tune. It delivers strong spool characteristics for towing use while supporting top-end airflow for performance driving. Step up to the Aurora Plus 7500 Compound Kit (202-972-2272) for a higher-output 5.9L build running 300-over or larger injectors -- this kit supports substantially more airflow at the top end for builds targeting maximum street power. For those who need a staged approach to a compound system, the ATS Aurora 4000/7500 Compound Kit (202-A47-2272) pairs a 4000-series high-pressure turbo with a 7500-series atmosphere unit for builds where a larger primary makes more sense for the power target.

For the 6.7L Cummins (2007.5-2009), the ATS Aurora Plus 5000 Compound Kit (202-952-2326) is the compound upgrade path for the early 6.7L. It pairs a performance atmosphere turbo with the factory high-pressure unit for improved spool and top-end airflow on a tuned early 6.7L.

For the early 5.9L (1994-1998), the ATS Aurora 3000/5000 Compound Kit (202-A35-2164) matches the fuel capacity and power targets of the P-pump platform at stage 2-3 tune levels.

Match the Turbo to the Build

Choosing the best Cummins turbocharger kit means matching it to the complete build, not just the power number:

• Injector sizing first: A turbo upgrade that outpaces the injectors produces air without enough fuel to burn it efficiently. Match the turbo tier to the injector size so the compressor map and the fuel system stay in proportion. The Aurora Plus 5000 works well with 200-250-over injectors. The 7500 kit suits 300-over and larger sets.
• Lift pump and CP3: On any tuned 5.9L or 6.7L Cummins, a FASS or AirDog lift pump protects the CP3 from inlet starvation under high-demand conditions. A compound turbo build demands consistent fuel delivery at high airflow rates -- do not skip the lift pump.
• Intercooler capacity: A larger turbo moves more compressed air at higher temps. A quality intercooler upgrade keeps intake charge temperatures low under sustained load and protects the engine from heat soak that limits power on long pulls.
• Tune calibration: A compound turbo or manifold package without a matching tune produces boost the ECM does not know how to manage. Work with a tuner experienced on the platform to set boost targets, fueling, and timing to match the new turbo's compressor map.

Browse turbocharger actuators and turbo hardware for VGT actuators, rebuild kits, and supporting components.

Signs Your Cummins Turbo Needs Attention

Watch for these symptoms on both the 5.9L and 6.7L platforms:

• Low boost pressure or a gauge reading consistently below target on a known-good tune
• Excess black smoke under load that does not clear with increased throttle
• Sluggish spool or turbo lag where response was previously sharp
• Boost fault codes -- P0234, P0299, or VGT-related fault codes on the 6.7L
• Oil contamination in the charge air piping or intercooler -- indicates a failed turbo seal
• Audible whine, grinding, or chirp from the turbo at any RPM
• Elevated EGTs at normal towing load compared to a known baseline

A VGT that stops responding to actuator commands produces unpredictable boost behavior and typically triggers limp mode under load. Before assuming turbo failure, verify the actuator is moving the vane ring freely. A seized vane ring on an otherwise healthy cartridge can sometimes be freed with cleaning and proper oil maintenance rather than full replacement.

Frequently Asked Questions

Does a compound turbo require custom piping on the 5.9L?

ATS Aurora compound kits for the 5.9L include all required piping, couplers, and hardware for a complete installation. No custom fabrication is needed. Most installs are completed with basic hand tools in a day-long shop session.

Is the BD Diesel Screamer package a full turbo replacement?

Yes. The BD Diesel Screamer manifold package includes both the exhaust manifold and the upgraded turbocharger as a matched system. Installing just the manifold or just the turbo separately does not achieve the same result -- the two components are matched for flow characteristics and must be installed together.

Can the ATS Aurora Plus 7500 be used on a daily-driven 5.9L?

The 7500-series atmosphere turbo is sized for high-output builds. On a daily-driven truck with moderate injectors and a light tune, it may produce slower low-RPM spool than the 5000-series kit. The 7500 is best suited to builds where the injectors and tune are in the 300-over range or larger and top-end airflow is the priority.

Bottom Line

For a tuned 6.7L Cummins (2013-2018), the BD Diesel Screamer manifold package is the best Cummins turbocharger upgrade for owners who want bolt-on performance gains without converting to a compound system. For a 5.9L Common Rail build, the ATS Aurora Plus 5000 compound kit is the most popular choice for a street and tow truck running a stage 2-3 tune. Match the kit to the injectors, support it with a lift pump and quality tune, and the Cummins will deliver the performance the platform is capable of.