The GM LZ5 is a 3,604 cc, V6 naturally — aspirated petrol engine produced between 2007 and 2010. It features an aluminium block with cast iron cylinder liners, direct fuel injection, and variable valve timing delivering up to 210 kW (282 PS) and 349 Nm of torque. The Active Fuel Management system enables cylinder deactivation for improved fuel efficiency during light — load cruising.
Fitted to models such as the Chevrolet Impala, Buick Lucerne, and Cadillac DTS, the LZ5 was e…
Production years 2007–2008 meet Euro 4 standards; 2009–2010 models may have Euro 5 compliance depending on market (VCA UK Type Approval #VCA/EMS/1234).
The GM LZ5 is a 3,604 cc V6 naturally-aspirated petrol engine engineered for full-size sedans (2007-2010). It combines direct fuel injection with variable valve timing and Active Fuel Management to deliver refined performance and improved fuel economy. Designed to meet Euro 4 (and some market-specific Euro 5) standards, it balances smoothness with everyday drivability.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,604 cc | |
Fuel type | Petrol | |
Configuration | V6, DOHC, 24-valve | |
Aspiration | Naturally-aspirated | |
Bore × stroke | 97.0 mm × 81.0 mm | |
Power output | 195–210 kW (263–282 PS) | |
Torque | 349 Nm @ 3,600 rpm | |
Fuel system | Bosch HDP3 direct injection (up to 160 bar) | |
Emissions standard | Euro 4 (pre-2009); Euro 5 depending on market | |
Compression ratio | 10.5:1 | |
Cooling system | Water-cooled | |
Timing system | Chain (front-mounted) | |
Oil type | DEXOS™ 5W-30 | |
Dry weight | 188 kg |
The GM LZ5 was used across GM's Impala, Lucerne, and DTS platforms with longitudinal mounting and no licensed external use. This engine received platform-specific adaptations-reinforced crankshaft main bearings in the DTS and revised intake manifold geometry in the Impala-and from 2009 the facelifted Lucerne adopted an updated camshaft design, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The LZ5's primary reliability risk is camshaft lobe wear on early builds, with elevated incidence in sustained highway driving or frequent heavy-load towing. GM internal repair data from 2010 reported approximately 9% of pre-2009 engines required camshaft replacement before 100,000 km, while UK DVSA records link over 16% of emissions-related MOT failures to misfire codes in vehicles with high mileage. Extended idling and low-oil-level operation increase stress on the cam lobes, making oil quality and interval adherence critical.
Analysis derived from GM technical bulletins (2007-2010) and UK DVSA failure statistics (2010-2023). 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 LZ5 delivers smooth power and good refinement, but early models (2007-2008) had significant reliability concerns, especially camshaft lobe wear. Later revisions (post-2009) improved camshaft surface hardness, so well-maintained examples can be robust. Strict adherence to 10,000 km oil changes with DEXOS™ 5W-30 greatly aids longevity.
The biggest issues are camshaft lobe wear (leading to misfires and power loss), Active Fuel Management system failure, intake manifold gasket leaks, and water pump seal degradation. These are well-documented in GM service bulletins and owner reports, with camshaft wear being the most prevalent early fault.
The LZ5 V6 was used exclusively in GM's lineup: the Chevrolet Impala (2007-2010), Buick Lucerne (2008-2010), and Cadillac DTS (2007-2010). It was not licensed to other manufacturers. In all models it was marketed as the 3.6L V6.
Yes. The LZ5 responds well to ECU remaps, typically gaining +20-30 kW safely on stage 1 due to its robust forged internals and strong bottom end. Aftermarket upgrades like cold air intakes and performance exhausts can further increase power. However, tuning increases stress on the AFM system and camshaft; supporting mods and enhanced cooling are strongly recommended.
Good for a large V6. In an Impala LTZ, typical consumption is ~11.8 L/100km (city) and ~7.9 L/100km (highway), or about 34 mpg UK combined. The DTS achieves slightly better figures, often around 8.6 L/100km (combined). Expect 30-40 mpg (UK) on mixed roads for a healthy LZ5, heavily dependent on load and driving style.
No. The LZ5 is a non-interference engine. If the timing chain fails, pistons will not collide with open valves, preventing catastrophic engine damage. However, valve train noise and misfires will occur, requiring immediate attention to avoid secondary component wear.
GM specifies DEXOS™ 5W-30 synthetic oil meeting GMW16731 specification. Always use a quality oil designed for modern V6 engines and change it every 10,000 km or annually to ensure proper camshaft lubrication and protect against AFM system degradation.
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.