Hyundai / Genesis / Kia Turbocharger Rebuild

Theta II to
Lambda 3.3T.

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.

Theta II 2.0T Smartstream 2.5T Lambda 3.3T Twin Genesis G70 / G80 Kia Stinger Sonata / Optima
Start Your Rebuild 813-443-0531
Theta II Engine Recall -- Turbo Implications
The Theta II 2.0T and 2.4L engines were subject to a major recall involving metallic debris from the manufacturing process remaining in the crankshaft oil passages. This debris restricts oil flow to connecting rod bearings, causing progressive bearing wear that eventually leads to catastrophic engine failure. When a Theta II engine suffers a connecting rod bearing failure, the resulting metal contamination travels through the oil system -- including through the turbocharger oil supply. Any Theta II turbocharger from an engine that has experienced bearing-related noise, oil consumption, or a recall-related repair should be inspected before returning to service. Engine debris that reaches the turbo bearings causes the same progressive wear in the turbo that it caused in the engine.
Lambda 3.3T Oil Feed Pipe Recall -- NHTSA 24V191 / 24V169
An active safety recall affects the Lambda II 3.3T twin turbo V6 on the Genesis G70, G80, G90, Kia Stinger, and Kia K900. The left-hand turbocharger oil feed pipe can crack from heat exposure and leak oil directly onto the exhaust manifold, creating a fire hazard. Hyundai part number 28240-3L100 covers the oil feed pipe and hose assembly. If your 3.3T vehicle has not had this recall performed, Kia and Genesis recommend parking outdoors and away from structures until the repair is completed. We inspect the oil feed pipe at every 3.3T turbo rebuild as a standard step regardless of recall status.
Engine Families
Three Platforms,
One Shop

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.

2009 — Present
Theta II 2.0T
Mitsubishi TD04 • MHI Twin-Scroll • 2.0L I4

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.

Hyundai Genesis Coupe 2.0T2010-2016
Hyundai Sonata 2.0T Sport2013-2019
Hyundai Tucson 2.0T2016-2021
Kia Optima 2.0T SX / Limited2011-2020
Kia Sportage 2.0T SX2011-2016
Kia Stinger 2.0T2018-2023
Genesis G70 2.0T2019-2023
Mitsubishi TD04 Twin-Scroll
2018 — Present
Smartstream 2.5T
BorgWarner • Single Twin-Scroll • 2.5L I4

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 (CVVD) system. No major recall history as of yet. Rebuild support fully available through BorgWarner components.

Hyundai Sonata N-Line / SEL Plus2021-present
Hyundai Santa Fe 2.5T AWD2021-present
Kia K5 GT / Sportage X-Pro2021-present
Kia Sorento X-Line 2.5T2021-present
Genesis G70 2.5T (facelift)2022-present
Genesis GV70 2.5T / GV80 2.5T2021-present
BorgWarner Twin-Scroll
2015 — Present
Lambda II 3.3T
Garrett GT14 • Twin Turbo V6 • 3.3L

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 24V191/24V169) is platform-critical -- see the notice above. OEM part numbers: 28231-3L000 (left) and 28231-3L010 (right) for G70/G80/Stinger applications. Garrett GT14 left: TUR-105897-GTN; right: TUR-105894-GTN.

Kia Stinger GT / GT1 / GT22018-2023
Kia K900 3.3T2019-2020
Genesis G70 3.3T Sport2019-2023
Genesis G80 3.3T Sport2017-2023
Genesis G90 3.3T2017-2022
Garrett GT14 Twin
Application Reference
Hyundai / Genesis / Kia
Cross Reference

Search by model, year, engine, or turbo to identify your application before submitting a rebuild request.

TurboApplicationYearsEngineMfrKey OEM PNs
TD04-13THyundai Genesis Coupe 2.0T2010-2012G4KF • Theta IIMHI28231-2CM00 / 28231-2CM01
TD04-19THyundai Genesis Coupe 2.0T (facelift)2012-2016G4KH • Theta II T-GDIMHI28231-2CTA0 / 28231-2CTA2
TD04-19THyundai Sonata 2.0T Sport / Limited2013-2019G4KH • Theta II T-GDIMHI28231-2CTA0
TD04-19THyundai Tucson 2.0T2016-2021G4KH • Theta II T-GDIMHI28231-2CTA0
TD04-19TKia Optima 2.0T SX / Limited2011-2020G4KH • Theta II T-GDIMHI28231-2CTA0 / 853073-0003
TD04-19TKia Sportage 2.0T SX2011-2016G4KH • Theta II T-GDIMHI28231-2CTA0
TD04-19TKia Stinger 2.0T (base)2018-2023G4KH • Theta II T-GDIMHI28231-2CTA2 / 853073-5003
TD04-19TGenesis G70 2.0T (base)2019-2023G4KH • Theta II T-GDIMHI28231-2CTA2 / 853073-9003
BW 2.5THyundai Sonata N-Line / SEL Plus2021-presentG4KP • Smartstream 2.5TBorgWarner28231-2S400
BW 2.5THyundai Santa Fe 2.5T AWD2021-presentG4KP • Smartstream 2.5TBorgWarner28231-2S400
BW 2.5TKia K5 GT / Sorento X-Line 2.5T2021-presentG4KP • Smartstream 2.5TBorgWarner28231-2S400
BW 2.5TGenesis G70 2.5T / GV70 2.5T / GV80 2.5T2022-presentG4KR • Smartstream 2.5TBorgWarner28231-2S400
Garrett GT14 (L)Kia Stinger GT / K900 / G70 / G80 / G90 3.3T2018-2023G6DP • Lambda II 3.3TGarrett28231-3L000 / TUR-105897-GTN
Garrett GT14 (R)Kia Stinger GT / K900 / G70 / G80 / G90 3.3T2018-2023G6DP • Lambda II 3.3TGarrett28231-3L010 / TUR-105894-GTN
Garrett GT14 (L)Genesis G90 3.3T2017-2022G6DP • Lambda II 3.3TGarrett28231-3L000 • Oil line recall: 28240-3L100
Showing all 15 applications
Failure Analysis
How These Turbos
Fail
01
Engine Debris Contamination (Theta II)
Theta II 2.0T • All Applications
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.
02
Lambda 3.3T Oil Feed Pipe Failure
Lambda II 3.3T • Stinger / G70 / G80 / G90
The left-side turbocharger oil feed pipe on the 3.3T twin turbo V6 is subject to an active recall (NHTSA 24V191/24V169). 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. Left turbo showing more wear than the right on a 3.3T is a common indicator of feed pipe restriction.
03
Oil Starvation from Extended Service Intervals
All Platforms
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.
04
Hot Shutdown Damage
All Platforms
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.
05
Compressor Wheel Damage (FOD)
All Platforms
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.
06
Wastegate Actuator Wear (Lambda 3.3T)
Lambda II 3.3T • Garrett GT14
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.

Send Us Your
Hyundai, Genesis, or Kia

Start a rebuild request online. Ship your turbo or turbos to Dade City, FL. We handle teardown, documentation, rebuild, and VSR balancing.

Start Your Rebuild 813-443-0531
37833 Pineapple Ave Unit A • Dade City, FL 33523 • sales@theboostlab.com