Powertrains
Holden, recognising the risks of simultaneously introducing a new platform and drivetrain, introduced the Australian-built Alloytec V6 engine derived from the proven VZ model. Adapting a proven engine design lessened the likelihood that Holden would find, and have to rectify, faults before starting production. The original base V6 benefited from power increases compared to the VZ, with engine noise decreased by implementing new timing chains, among other modifications. The four-speed GM 4L60-E automatic transmission—earlier iterations of which were first introduced to the Commodore in 1988 with the VN series—remained for this engine, with subtle alterations to its functionality.[47][48][49] Manual transmission options were the six-speed Aisin AY6 (available with the High Output Alloytec V6) and Tremec TR6060 six-speed (for the V8), while two automatics featuring Active Select functionality were offered as the five-speed GM 5L40-E (for the High Output Alloytec V6) and six-speed GM 6L80-E (for the V8). At launch for the VE, the February 2006 onwards VZ's L76 V8 engine was eschewed in lieu of the L98, which did not include the fuel-saving Active Fuel Management (AFM) technology included with the L76.[50][51]
In October 2006 Holden introduced a bi-fuel variant of the Alloytec V6, offered in the Omega and Berlina variants. This version can run on both petrol and LPG, incorporating an advanced Sequential Vapour Gas Injection system and reinforced valve seats for durability. The bi-fuel V6 delivers slightly lower performance—5 kW and 5 Nm less than the conventional V6 when running on LPG—resulting in a total of 175 kW. The engine uses a large 100 kg cylindrical gas tank, which results in decreased boot space and slightly increased fuel consumption.[52][53] On 16 October 2006, due to a faulty fuel hose that caused a fuel smell to enter the cabin, a recall was issued that affected 1,521 V8 Commodore and WM Statesman/Caprice models,[54] On 10 November 2006, resulting from defective rear seat belt anchors, a second recall was issued, which affected 12,830 Commodores and WM models built before 11 September 2006.[55] On 10 April 2007, due to the possibility that the bi-fuel Commodores may have been fitted with undersized O-rings in the service valve hand tap, Holden issued a recall affecting models produced between November 2006 and April 2007.[56]
On 21 October 2008, Holden disclosed the upgrades for the MY09.5 models. Alterations involved the standardisation of the Alloytec V6 across the entire Commodore range from November 2008, whereas it was previously exclusive to the SV6 and Calais.[59][60] The Omega and Berlina variants gained variable valve timing, but the "premium" dual exhaust system and the five-speed automatic were excluded. The upshot of this is an output reduction of 5 kW and 5 Nm compared to the engine it replaces. Omega and Berlina sedans and Sportwagons benefit from a two and four per cent fuel efficiency improvement, respectively.[61] Emissions had also been reduced, which allowed petrol-powered variants to achieve a Euro VI certification, an emission standard that was introduced in Europe in 2014. These changes extend further than the petrol engine, as bi-fuel LPG variants benefit from an eight per cent improvement in fuel economy when running on LPG.[62] The LPG models produce 318 Nm, which is 7 Nm less than before.[63] Also announced in 2008 was a version of the 6.0-litre V8 engine featuring General Motors' AFM technology, designated
On 4 August 2009, Holden announced the MY10 revisions to the VE and WM range.[66] For the Omega and Berlina, the 3.6-litre Alloytec V6 was superseded by a 3.0-litre engine, the lowest engine displacement of a Commodore since the straight-six engine fitted to the 1986 VL series. The new engine received Spark Ignition Direct Injection (SIDI) technology, claimed to yield a fuel consumption reduction of up to 12 percent. Power was increased to 190 kW, albeit with a reduction in torque to 290 Nm.[67] Along with the 3.0-litre engine, a newly-developed 3.6-litre version of the same, producing 210 kW and 350 Nm, was also unveiled. Other than the manual transmission version of the SV6, all SIDI V6 models are coupled to GM's 6L50 automatic transmissions and fall under Holden's EcoLine designation.[68] Benefits to fuel economy for the 3.6-litre SIDI can also be attributed to an improved "deceleration fuel cut" system, which halts the fuel supply during engine coasting, a more efficient alternator and voltage regulator, a 50 revolution per minute (rpm) reduction in idle speed (to 550 rpm), and the incorporation of a "turbine damper", for the automatic transmission, that suppresses vibrations at low RPMs, thus enabling earlier upshifts.
In late August 2010, significant updates were introduced with the MY11 Series II upgrades.[70] The Omega versions of the Ute were upgraded to the 3.0-litre SIDI engine paired with a six-speed automatic transmission, as used in the sedan and wagon versions.[71] Holden also modified the 3.0-litre V6 to accept E85 bio-ethanol, in addition to petrol, stating that using E85 provides a sizeable increase in performance and reduces emissions between 20 and 40 per cent, depending on the distance the fuel is transported from the production site to the filling station.[72] In September 2011, E85 compatibility was extended to the 3.6-litre V6 as part of the MY12 update.[73]
