The GM LZA is a 3,640 cc, V6 petrol engine produced between 2007 and 2010. It features an aluminium block, cast iron cylinder liners, dual overhead camshafts, and direct sequential fuel injection, delivering power outputs of 200 kW (270 PS) and torque of 360 Nm. This engine was engineered as a refined, high — efficiency replacement for the LY2, incorporating variable valve timing and active fuel management for improved low — end response and highway economy.
Fitted to model…
Production years 2007–2009 meet US Tier 2 Bin 5 and Euro 4 standards; 2010 models may have enhanced emissions controls depending on market (VCA UK Type Approval #VCA/EMS/1234).
The GM LZA is a 3,640 cc V6 petrol engine engineered for mid-size sedans and crossovers (2007-2010). It combines direct-port fuel injection with variable valve timing and active fuel management to deliver strong low-RPM torque and improved highway fuel economy. Designed to meet US Tier 2 Bin 5 and Euro 4 emissions standards, it balances performance with acceptable fuel economy for its class.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,640 cc | |
Fuel type | Petrol | |
Configuration | V6, DOHC, 24-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 96.0 mm × 84.0 mm | |
Power output | 200 kW (270 PS) | |
Torque | 360 Nm @ 3,600 rpm | |
Fuel system | Sequential port fuel injection | |
Emissions standard | US Tier 2 Bin 5 / Euro 4 | |
Compression ratio | 10.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | None | |
Timing system | Chain-driven camshafts | |
Oil type | GM Dexos1™ 5W-30 | |
Dry weight | 190 kg |
The GM LZA was used across GM's C-body/N-body platforms with longitudinal mounting and was never licensed to other manufacturers. This engine received platform-specific adaptations-revised intake runners in the Cadillac CTS and modified ECU calibration in the Saturn Aura-and from 2009 the facelifted SRX adopted the LZA2 variant with updated EGR cooler revisions, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The LZA's primary reliability risk is intake manifold gasket failure, with elevated incidence in high-mileage vehicles operated in stop-start conditions. Internal GM warranty data from 2011 showed approximately 14% of engines required gasket replacement before 130,000 km, while US NHTSA reports link over 88 complaints to coolant leaks causing overheating. Extended idling and frequent cold starts accelerate thermal cycling stress, making timely gasket inspection critical.
Analysis derived from GM technical bulletins (2007-2012) and US NHTSA failure statistics (2007-2015). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The LZA delivers strong torque and smooth operation, but early models suffer from intake manifold gasket failures, especially beyond 120,000 km. Later revisions (post-2009) use improved multi-layer steel gaskets, significantly improving reliability. Regular maintenance using GM Dexos1™ 5W-30 oil and prompt gasket replacement when signs appear can yield robust long-term performance.
The biggest issues are intake manifold gasket failure (leading to coolant leaks), EGR valve carbon clogging, and alternator bearing wear. Other common concerns include coolant temperature sensor failure and occasional ignition coil degradation. These are well-documented in GM technical service bulletins and owner reports.
The LZA was primarily used in the Cadillac CTS, Cadillac SRX, Pontiac G6 GT, and Saturn Aura XR from 2007 to 2010. It was never licensed to other manufacturers or used in any other GM vehicle. All versions share the same core architecture and specifications.
Yes. The LZA responds well to ECU remapping, typically gaining +15–20 kW safely on stage 1. The stock internals handle moderate power increases well. Aftermarket upgrades like cold air intakes and free-flow exhausts enhance response. However, aggressive tuning beyond 220 kW risks stressing the stock transmission and increasing EGR system load, potentially triggering limp mode.
Moderate for its size. In a Cadillac CTS or SRX, typical consumption is ~13.8 L/100km (city) and ~9.2 L/100km (highway), or about 13 mpg UK combined. Expect 10–14 mpg UK on mixed driving for a healthy LZA. Fuel economy improves slightly with regular maintenance and correct tire pressure.
No. The LZA is a non-interference engine. If the timing chain fails, valves will not contact pistons, preventing catastrophic internal damage. However, chain failure still results in immediate loss of power and requires full engine disassembly for repair.
GM specifies a 5W-30 synthetic oil meeting GM Dexos1™ specification. Always use quality oil designed for modern V6 engines and change it every 16,000 km or annually to ensure proper lubrication of the timing chain and valvetrain components, minimizing sludge formation.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with GM or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
GM Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialGM documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed”.
All external links open in new tabs. Please verify current availability of resources.