Twin Turbocharger R2S for International 4300 4400 7300 7400 (2010-2017) 7.6L

Direct-Replacement R2S Twin Turbocharger Assembly for 2010-2017 International 4300, 4400, 7300, 7400 (DuraStar / WorkStar)

What it Does: The R2S twin turbocharger assembly replaces the complete dual-stage forced induction system on 2010-2017 International medium-duty trucks to restore factory manifold boost pressure, resolve soot-induced actuator binding, and eliminate power loss under heavy payload conditions.

The Stock International 4300, 4400, 7300, 7400 Turbocharger Failure Modes

The EPA10 MaxxForce DT (I334) 7.6L inline-six relies on a regulated two-stage (R2S) system subjected to extreme exhaust gas recirculation (EGR) heat and heavy cycling. The factory high-pressure (HP) and low-pressure (LP) layout commonly experiences severe carbon fouling across the interstage bypass valve, causing the internal wastegate and flapper assembly to stick. Concurrently, excessive heat soak degrades the journal and thrust bearings inside the center housing rotating assemblies (CHRA), causing axial shaft play, oil seal deterioration, blow-by through the intercooler piping, and diagnostic fault codes such as low boost or EGR delta-P errors.

The Engineering Solution

This replacement assembly delivers a factory-calibrated, complete two-stage drop-in solution. Manufactured with high-nickel ductile iron turbine housings to withstand sustained EGTs without micro-fracturing, each CHRA is dynamic VSR balanced to prevent high-RPM harmonic vibration. The internal bypass actuator and ducting arrive pre-indexed and synchronized, restoring instantaneous spool response from the high-pressure unit while ensuring full exhaust gas flow to the low-pressure turbine during sustained heavy-duty highway pulling.

What's Included

• 1x Complete R2S Two-Stage Twin Turbocharger Assembly (High-Pressure Turbo, Low-Pressure Turbo, Interstage Connection Duct, and Pre-Installed Bypass Actuator)

Technical Specifications

Compatibility

• 2010-2017 International 4300 (MaxxForce DT 7.6L Diesel)
• 2010-2017 International 4400 (MaxxForce DT 7.6L Diesel)
• 2010-2017 International 7300 (MaxxForce DT 7.6L Diesel)
• 2010-2017 International 7400 (MaxxForce DT 7.6L Diesel)

Frequently Asked Questions & Fitment Warnings

Does this fit the DuraStar / WorkStar 4300, 4400, 7300, 7400?

Yes, this is a direct fit for 2010-2017 models equipped with the EPA10 MaxxForce DT 7.6L (I334) engine. It does not fit pre-2010 EPA07 single-turbo setups or MaxxForce 9/10 engines with differing turbine housing flanges.

What pre-installation steps are mandatory before initial startup?

You must change engine oil and filters, flush or replace oil feed and drain lines, inspect the charge air cooler for trapped oil debris, and manually prime both turbo center housings with clean oil prior to cranking.

The International Commercial Standard

Built for rigorous commercial cycles, severe duty towing, and high-hour municipal use, this complete turbocharger assembly maintains consistent thermal stability and boost performance without core return requirements.