Duramax LMM and LML are 4th generation engines manufactured by General Motors (GM). Duramax LMM is the earlier version of Duramax LML and was first introduced in 2007, whereas Duramax LML was first introduced in the 2011 model year.
As an updated version of LMM, Duramax LML offers several improvements over LMM. I have outlined the similarities and differences between LMM and LML in this article.
LMM Vs LML [10 Must-Know Differences]
There are 10 must-know differences between Duramax LMM and LML in terms of pricing, horsepower, vehicle application, durability, mpg, mph, longevity, towing capacity, etc.
Here is a quick comparison of LMM and LML engines:
Duramax LMM Engine |
Feature |
Duramax LML Engine |
365 hp or 272 kW |
Horsepower |
397 hp or 296 kW |
606 lb-ft or 895 Nm |
Torque |
765 lb-ft or 1037 Nm |
15 mpg/city and 19 mpg/highway |
Fuel Economy |
16 mpg/city and 21 mpg/highway |
5.8 seconds |
0-60 mph |
5.6 seconds |
13,000 pounds or 5896.7 kg |
Towing Capacity |
14,500 pounds or 6,577 kg |
$9,500-$10,000 |
Price |
$13,000 |
5 years or 100,000 miles, whichever comes first |
Basic Warranty |
5 years or 150,000 miles, whichever comes first |
300,000 miles |
Longevity |
300,000-400,000 miles |
3250 RPM |
Maximum Engine Speed |
3000 RPM |
01. Vehicle Application of Duramax LMM and LML
Duramax LMM engines are used in mid-2007 GM vehicles, while Duramax LML engines are used in 2011 model year GM vehicles.
Let’s take a look at the vehicle applications of both engines separately.
The Duramax LMM engine powers the following GM vehicles:
- Chevrolet Silverado HD [2007.5-2010]
- GMC Sierra HD [2007.5-2010]
- Chevrolet Kodiak
- GMC Topkick
- Chevrolet Express
- GMC Savana
The Duramax LML engine powers the following GM vehicles:
- Chevrolet Silverado HD [2011-2016]
- GMC Sierra HD [2011-2016]
02. LMM Horsepower Vs LML Horsepower
GM’s 6.6L LMM V-8 Duramax turbo diesel engine’s maximum horsepower is 365 hp (or 272 kW) at 3200 RPM.
On the other hand, the GM 6.6L LML V-8 Duramax turbo diesel engine’s maximum horsepower is 397 hp (or 296 kW) at 3000 RPM.
The LML engine provides 32 hp more than the Duramax LMM engine.
03. LMM Duramax MPG Vs LML Duramax MPG
Mileage is an influential factor in determining the differences between two engines. A high-mileage truck means high fuel efficiency, saving you a lot of money. This is why many users prefer vehicles with high mileage.
LMM diesel engine provides approximately 15 mpg in the city and 19 MPG on the highway.
On the other hand, the LML diesel engine provides approximately 16 mpg in the city and 21 MPG on the highway.
Regarding fuel economy, Duramax LML proved to be more fuel efficient than Duramax LMM.
04. LMM Duramax 0-60 Vs LML Duramax 0-60
The Duramax LMM engine reaches 0-60 mph in about 5.8 seconds. On the other hand, the estimated time for the Duramax LML engine to reach 0-60 mph is about 5.6 seconds. LML is faster than Duramax LMM by 0.2 milliseconds.
The following video will provide you with additional information about LML Vs LMM 0-60 mph:
05. LMM Duramax Towing Capacity Vs LML Duramax Towing
Towing capacity is a crucial characteristic of a truck that plays a significant role when purchasing trucks. The Duramax LMM diesel engine’s towing capacity is about 13,000 pounds or 5896.7 kilograms.
Duramax LMMs can tow 16,500 pounds or 7,484 kilograms with a fifth-wheel hitch. In contrast, the Duramax LML diesel engine’s towing capacity is up to 14,500 pounds or 6,577 kilograms.
With 5th-wheel hitches, the Duramax LML can tow around 18,000 pounds. Duramax LML can tow up to 1,500 pounds more than Duramax LMM.
06. LMM Price Vs LML Price
The Duramax LMM market price is around $9,500 to $10,000. The brand-new Duramax LML’s current market price is approximately $13,000. There’s a $3,000 price difference between the Duramax LML and Duramax LMM.
07. LML Duramax Warranty Vs LMM Duramax Warranty
Depending on the part, the warranty period and range will vary. GM offers specific warranties for specific parts. If we consider the average warranty period for both engines, we can say:
GM provides a 5-year or 100,000-mile warranty for Duramax diesel LMM engines. In contrast to LMM, the Duramax LML engine provides 150,000 miles or 5 5-year warranty, whichever comes first.
As a result, the Duramax LML engine has a slight advantage over the Duramax LMM engine in terms of the warranty.
08. LMM Duramax Longevity Vs LML Duramax Longevity
It’s common for Duramax LMM engines to last over 300,000 miles (482,803 km) without any major servicing issues.
In contrast, a well-maintained Duramax LML engine can last 300,000 miles (482,803 km) to 400,000 miles (643,738 km) without major engine issues.
However, some Duramax owners claim their engines have lasted more than 500,000 miles (804,672 km) without any major engine problems.
When it comes to longevity, Duramax’s LMM and LML diesel engines are among the most reliable diesel engines on the market.
09. LMM Torque Specs Vs LML Torque Specs
The Duramax LMM engine provides 606 lb-ft or 895 Nm at 1600 RPM. Alternatively, the Duramax LML engine provides up to 765 lb-ft or 1037 Nm at 1600 RPM. So, in terms of acceleration, the Duramax LML engine wins.
10. Max Engine Speed
Duramax LMM’s maximum engine speed is 3250 RPM. Duramax LML’s maximum engine speed is 3000 RPM.
The Duramax LML engine provides more power at a lower RPM. That’s why LML has better fuel efficiency.
Watch the video given below to learn more about LMM Vs LML Duramax:
Which is Better LMM or LML?
The Duramax 6.6L LML diesel engine is an updated version of the Duramax LMM. If we consider fuel economy, the LML engine provides 11% better fuel economy than the LMM.
Duramax LML engine is better than the LMM engine in terms of horsepower and towing capacity. In terms of pricing, the Duramax LML is more expensive than the Duramax LMM. Overall, comparing many aspects, it’s clear that the Duramax LML diesel engine is better than the Duramax LMM.
FAQs
What year is the LMM Duramax?
The LMM Duramax is a mid-2007 to 2010 model-year engine.
Duramax LMM engines were available in Chevrolet Silverado HD and GMC Sierra HD models from 2007 to 2010.
Is the LMM a good Duramax?
The Duramax LMM engine has overcome many issues compared to its previous version, the Duramax LBZ engine.
LMM Duramax has a long lifespan and is a mid-level reliable engine compared to the latest Duramax engines.
Is the LML the best Duramax?
No, actually, there are better engines than LML from Duramax.
Duramax L5P and recent engine models are superior to Duramax LML.
But GM’s Duramax LML is an impressive improvement over its predecessor.
Although the Duramax LML has an emission protection system, it has better fuel economy.
Duramax LML has a few problems like any other engine, such as injection pump failure.
What does Duramax LMM mean?
To reduce nitrogen oxides and particulate matter emissions from light trucks, the EPA-mandated Duramax LMM came in 2007.
It is a lightweight diesel engine.
How much HP can LMM handle?
LMM can handle up to 540 RWHP (Rear Wheel Horsepower).
You need a bigger pump to get more horsepower.
ATS add-a-pump kit or Exergy Stroker CP4 can help you achieve your goal.
How long will a Duramax LMM last?
A Duramax LMM lasts over 300,000 miles (482803 km) without any major issues.
For this milestone to be achieved, proper maintenance must be carried out.
How long do injectors last on LMM?
In my experience, Duramax LMM injectors last at most 100,000 to 120,000 miles.
Duramax LMM injectors should last as long as the vehicle but must be maintained.
It is possible that sometimes you will need to change the injectors of your Duramax LMM, which is a rare occurrence.
Read More:
- 9 Differences Between LB7 and LBZ
- 10 Differences Between LML and L5P
- 12 Differences Between LLY and LBZ
Final Thoughts
If you already own a Duramax LML or LMM, there is no need to worry; both engines are reliable for the model years in which they were designed.
Despite the reliability of both engines, you should choose the Duramax LML engine over the LMM if you must choose between them.
When it comes to power output and fuel economy, the LML Duramax is slightly ahead of the LMM.