From the Theta II 2.0T found in millions of Sonatas and Optimas to the Garrett GT14 twin turbos in the Stinger, G70, and G80, Boost Lab rebuilds the full Hyundai, Genesis, and Kia turbocharged lineup. The Theta II recall history means a lot of these engines have already been through significant stress. We know what that does to a turbocharger.
Three distinct turbocharged engine families span the Hyundai, Genesis, and Kia lineup. Each uses a different turbocharger manufacturer and has its own failure patterns and rebuild considerations.
The Theta II 2.0T uses a Mitsubishi TD04-based twin-scroll turbocharger integrated with the exhaust manifold as a combined cast unit. The early G4KF (2009-2011) produces 210-223hp on the Genesis Coupe. The updated G4KH T-GDI (2012 onward) stepped to direct injection and raised output to 274hp on 18psi. The turbocharger and exhaust manifold are cast as a single piece: a combined unit that must be replaced or rebuilt together. Mitsubishi TD04 rebuild components are available and the platform is fully serviceable.
The Smartstream G2.5T replaced the Theta II as the performance four-cylinder across the Hyundai, Kia, and Genesis lineup from 2018 onward. Uses a BorgWarner twin-scroll turbocharger bolted directly to the cylinder head with integrated cooling passages. The 2.5T is widely regarded as a significant improvement over the Theta II in both reliability and performance. Combined port and direct injection with CVVD. No major recall history as of yet. Rebuild support fully available through BorgWarner components.
The Lambda II 3.3T twin-turbocharged V6 is the performance flagship across the Genesis and Kia performance lineup. Uses a pair of Garrett GT14 turbochargers with electronic wastegate actuators, one per bank, in a true twin configuration. Always rebuild both turbos together. The left-side oil feed pipe recall (NHTSA 24V191 and 24V169) is platform-critical: see the notice above. OEM part numbers: 28231-3L000 (left) and 28231-3L010 (right) for G70, G80, and Stinger applications. Garrett GT14 left: TUR-105897-GTN; right: TUR-105894-GTN.
Search by model, year, engine, or turbo to identify your application before submitting a rebuild request.
| Turbo | Application | Years | Engine | Mfr | Key OEM PNs |
|---|---|---|---|---|---|
| TD04-13T | Hyundai Genesis Coupe 2.0T | 2010-2012 | G4KF, Theta II | MHI | 28231-2CM00 / 28231-2CM01 |
| TD04-19T | Hyundai Genesis Coupe 2.0T (facelift) | 2012-2016 | G4KH, Theta II T-GDI | MHI | 28231-2CTA0 / 28231-2CTA2 |
| TD04-19T | Hyundai Sonata 2.0T Sport / Limited | 2013-2019 | G4KH, Theta II T-GDI | MHI | 28231-2CTA0 |
| TD04-19T | Hyundai Tucson 2.0T | 2016-2021 | G4KH, Theta II T-GDI | MHI | 28231-2CTA0 |
| TD04-19T | Kia Optima 2.0T SX / Limited | 2011-2020 | G4KH, Theta II T-GDI | MHI | 28231-2CTA0 / 853073-0003 |
| TD04-19T | Kia Sportage 2.0T SX | 2011-2016 | G4KH, Theta II T-GDI | MHI | 28231-2CTA0 |
| TD04-19T | Kia Stinger 2.0T (base) | 2018-2023 | G4KH, Theta II T-GDI | MHI | 28231-2CTA2 / 853073-5003 |
| TD04-19T | Genesis G70 2.0T (base) | 2019-2023 | G4KH, Theta II T-GDI | MHI | 28231-2CTA2 / 853073-9003 |
| BW 2.5T | Hyundai Sonata N-Line / SEL Plus | 2021-present | G4KP, Smartstream 2.5T | BorgWarner | 28231-2S400 |
| BW 2.5T | Hyundai Santa Fe 2.5T AWD | 2021-present | G4KP, Smartstream 2.5T | BorgWarner | 28231-2S400 |
| BW 2.5T | Kia K5 GT / Sorento X-Line 2.5T | 2021-present | G4KP, Smartstream 2.5T | BorgWarner | 28231-2S400 |
| BW 2.5T | Genesis G70 2.5T / GV70 2.5T / GV80 2.5T | 2022-present | G4KR, Smartstream 2.5T | BorgWarner | 28231-2S400 |
| Garrett GT14 (L) | Kia Stinger GT / K900 / G70 / G80 / G90 3.3T | 2018-2023 | G6DP, Lambda II 3.3T | Garrett | 28231-3L000 / TUR-105897-GTN |
| Garrett GT14 (R) | Kia Stinger GT / K900 / G70 / G80 / G90 3.3T | 2018-2023 | G6DP, Lambda II 3.3T | Garrett | 28231-3L010 / TUR-105894-GTN |
| Garrett GT14 (L) | Genesis G90 3.3T | 2017-2022 | G6DP, Lambda II 3.3T | Garrett | 28231-3L000, oil line recall: 28240-3L100 |
No results for your vehicle? Contact us at sales@theboostlab.com with your model and engine code and we can identify your unit.
The Theta II recall involved metallic debris from the manufacturing process remaining in the crankshaft oil passages. When bearing failure occurs, this debris travels through the oil system and into the turbocharger. A Theta II turbo from an engine with bearing-related history is compromised regardless of how it sounds. Debris in the turbo oil passages causes the same progressive wear it caused in the engine. At teardown we flush and inspect all oil passages and document bearing condition before quoting any repair.
The left-side turbocharger oil feed pipe on the 3.3T twin turbo V6 is subject to an active recall (NHTSA 24V191 and 24V169). The pipe deteriorates from heat exposure, cracks, and leaks oil onto the exhaust manifold, creating a documented fire risk. Oil starvation from a cracked feed pipe also damages the left turbo bearing. We inspect both oil feed pipes at every 3.3T rebuild. If the recall has not been performed, we flag it at teardown. A left turbo showing more wear than the right on a 3.3T is a common indicator of feed pipe restriction.
Hyundai and Kia factory oil change intervals are aggressive for turbocharged applications. Turbocharged engines run oil through the bearing housing at temperatures that degrade oil faster than a naturally aspirated engine of similar displacement. Owners following the factory oil life monitor on a Theta II or 3.3T and not performing regular oil analysis are running a risk. Carbon deposits from degraded oil in the bearing housing restrict flow and accelerate bearing wear on all three platforms. At rebuild, oil passage condition is documented and all passages are flushed.
Shutting down a turbocharged engine immediately after spirited driving allows residual heat to bake oil in the bearing housing with no oil flow. The Theta II and 3.3T are particularly relevant here because both platforms are popular with enthusiast drivers who push the cars hard. A 2-3 minute idle cooldown after sustained performance driving significantly extends turbo bearing life on all three platforms. The Smartstream 2.5T benefits from the same cooldown discipline.
Intake-side foreign object damage contacts the compressor wheel at operating speed. On the Theta II the combined turbo and manifold unit makes FOD inspection more involved at teardown: the assembly must be fully disassembled to inspect both the compressor and turbine wheels thoroughly. On the 3.3T, the left turbo is in a more exposed position and sees slightly more intake-side debris risk. Wheel condition is photographed and documented at teardown before any rebuild quote is issued.
The Garrett GT14 uses an electronic wastegate actuator. Actuator wear or failure presents as boost control irregularities, fault codes, or inconsistent power delivery. On tuned 3.3T applications running elevated boost, the actuator wears faster than stock. At every 3.3T rebuild both actuators are inspected and function-tested. A turbo returned with a worn actuator will present boost control issues on reinstallation regardless of the quality of the bearing rebuild.
Start a rebuild request online. Ship your turbo or turbos to Dade City, FL. We handle teardown, documentation, rebuild, and VSR balancing.
Start Your Rebuild37833 Pineapple Ave Unit A • Dade City, FL 33523 • sales@theboostlab.com