Overview
- Stepping in as a successor to the LMM Duramax in 2010, the LML Duramax was a cleaner, more powerful, and more efficient version of the diesel V8, compliant with the stringent Tier 2 anti-pollution norms.
- It was also the first wholly-designed engine by General Motors after its complete takeover of DMAX Limited, the company’s engine manufacturing unit at Moraine, Ohio.
While the inception of the Duramax V8 diesel engine with the LB7 Duramax was a landmark moment for Chevrolet, the first shot of massive popularity came a decade after with the LML Duramax. Essentially the fifth-generation version of the Duramax family of V8 diesel engines, the LML still ranks as one of the highest-selling Duramax engines ever.
We look at all the significant improvements introduced in the LML Duramax and how it became a massive chapter of success in the lineage of Duramax V8 diesel.
| Key details of LML Duramax V8 diesel engine | |
| Displacement | 6.6-liter/403 cu in |
| Chevy vehicles in which it was available | Silverado HD 2500, Silverado HD 3500 |
| Predecessor | LMM Duramax |
| Successor | L5P Duramax |
| Maximum power | 397 hp |
| Maximum torque | 765 lb-ft |
| Transmission | 6-speed Allison 1000 automatic |
History Of Chevrolet LML Duramax V8
Like other engines in the Duramax family, the LML Duramax also started as a brainchild of DMAX Limited in Moraine, Ohio. However, it was the first engine designed and engineered solely by General Motors when it took over the design department of DMAX in 2008, the year when the works on LML had begun.
While the previous-generation LMM served as the base for LML, General Motors did a lot of redesigning work to curb NVH levels and comply with the newer and stricter emission norms. After almost two years, General Motors debuted the LML Duramax V8 in 2010 for the 2011 model year of its full-size heavy-duty truck range.
Related: Everything about the Chevy Duramax 3.0 Diesel Engine
Which Chevrolet Vehicles Got The Duramax LML Diesel Engine?
When General Motors introduced the LML Duramax in 2010, it was immediately chosen as the flagship powertrain for the Chevrolet Silverado HD range, both 2500 and 3500 versions. The LML Duramax replaced the erstwhile-available LMM Duramax in the 2011 Chevrolet Silverado HD, the second-generation version.
This engine was retained in the third-generation Silverado HD, first introduced in 2013. However, in 2016, the LML Duramax was replaced by the all-new L5P series V8 with a mid-life update for the third-gen Silverado HD.
Chevy LML Duramax Engine Design: Key Details
While the base of the LML Duramax was the same 6.6-liter V8 block as its predecessor, the LMM Duramax, this Chevy V8 had a lot of redesigned elements and new add-ons. Making it a much cleaner and more efficient engine to meet the latest norms, the following are all those changes General Motors introduced with the LML Duramax V8:
- Addition of dual-loop EGR and SCR – By adding a dual-loop EGR system, General Motors managed to reduce NOx emissions by 63 percent compared to LMM, making the LML Duramax the cleanest diesel engine ever produced at that time. The NOx emissions were further controlled by the Selective Catalyst Reduction (SCR) system, making the LML Duramax the first Duramax diesel engine to get this tech.
- Ninth injector – The ‘ninth injector’ was added to the LML Duramax to supply raw fuel and diesel exhaust fluid (DEF) into the downstream exhaust to burn the trapped emission particulates accumulated in the diesel particulate filter, resulting in better combustion.
- Bosch CP4.2 fuel injection pump – This new pump introduced in the LML Duramax had the capacity to squeeze fuel up to 30,000 psi into the piezo-actuated fuel injection system.
- New crankshaft and connecting rods – The LML Duramax had a new nitride-hardened forged-steel crankshaft and new connecting rods with smaller pin bores on their smaller ends for better durability.
- Redesigned main bearings and oil pump – This Chevy engine also received five new main bearings and a higher-flowing oil pump for better lubrication of the rotating components.
- Honeywell AVNT (Garrett GT3788VA) Variable Vane Turbo (VVT) – This new-generation turbocharger introduced in the LML Duramax had an 11-blade 60.6mm inducer compressor wheel and 11.2mm tall vanes, compared to the 15mm tall vanes of the LLY’s turbocharger. These self-adjusting vanes of the turbocharger automatically alter the boost and backpressure of the turbo, thereby improving both power and fuel efficiency.
- New glow plugs – The fuel injection system was updated with new rapid-heating glow plugs, which helped in enhancing cold-weather starting performance.
- Redesigned air filter – Unlike the round air filter in previous-generation versions of Duramax, the LML received a flat-panel cartridge air filter, which helped prevent snow intake and resulted in better airflow.
Related: Everything about the Chevy TurboMax Engine
Performance Of Duramax LML V8: Power, Torque, Fuel-Efficiency
All the aforementioned changes and add-ons introduced in the LML Duramax over its predecessor improved its fuel efficiency by 11 percent while claiming higher power and torque outputs.
As said above, this engine was available in the Chevrolet Silverado HD between 2011 and 2016 and claimed 397 hp and 765 lb-ft.
Paired with a 6-speed Allison 1000 automatic transmission as standard, the LML Duramax delivers 16-17 mpg in city and up to 24 mpg in highway driving conditions.
Related: The Ultimate Guide to Towing with the Silverado 1500
Life Expectancy Of LML Duramax: Positives, Negatives, And Reliability
Over 600,000 LML Duramax engines were manufactured between 2011 and 2016, making it one of the highest-selling versions of the Duramax V8 diesel engines ever. Since it was sold in such large numbers, the LML Duramax carries a solid reputation for reliability.
Some owners of the Chevrolet Silverado HD with this V8 diesel engine have claimed to cover more than 200,000 miles in their pickup trucks in heavy-duty usage. Such extensive mileage is possible, provided the engine is regularly maintained. The improved fuel efficiency and power and torque outputs over the LMM further strengthened its desirability.
However, the engine had its minor share of concerns. The first-batch LML Duramax engines suffered from NOx sensor issues. General Motors quickly resolved these issues with updated sensors that claimed a longer warranty of 10 years or 100,000 miles. Also, the new Bosch CP4.2 fuel pump operated without a lift pump, which did reduce the NVH levels, but was also not as long-lasting as the previous-generation CP3 pump.
Related: Are Chevy Vehicles Really Reliable?
Conclusion: Is The LML Duramax A Good Engine?
In times when stricter emission norms were affecting the performance and fuel efficiency of diesel engines, the LML Duramax proved how effective changes can be made to balance out all things. While it was much cleaner and relatively more reliable than its predecessor, the LMM Duramax, it also claimed better power, torque, and fuel efficiency, proving its testimony to General Motors’ prowess in engine development.
FAQs
Q1. How many miles can you get out of an LML Duramax?
If regularly maintained, the LML Duramax can last hassle-free for more than 200,000 miles.
Q2. What problems does the LML Duramax have?
The earlier versions of the LML Duramax had NOx sensor issues, which were resolved quickly by General Motors with longer-lasting NOx sensors.
Q3. How much hp can an LML Duramax handle?
The LML Duramax produced 397 hp and 765 lb-ft in the Chevrolet Silverado HD.
Q4. What years is the LML Duramax?
The LML Duramax was available in the Chevrolet Silverado HD between 2011 and 2016.
Q5. How many litres is an LML Duramax?
Like other iterations of the Duramax V8 diesel engine, the LML Duramax was also a 6.6-liter engine.
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