6.5L GM Diesel Towing: Making the Grade

Can Your Diesel Make The Grade? A Five-Mile, Six Percent Mountain Grade in Washington State Puts Our Project 6.5L Suburban to the Test

Suburban Renewal walked you through the upgrade process for a stock 6.5L using a representative Suburban 4x4. In that article, we focused reporting on the overall reliability and performance improvements realized through the upgrades. While these are, of course, vital to the everyday use of your truck, we will now focus on the uphill, heavy towing performance gains realized as a result of the upgrades. For many of us, this is what matters the most and it is during these times of high stress that we want to be able to depend on our work trucks. We took the time to test the towing capabilities at both the near-stock configuration and after completing our regimen of upgrades. Looking at the results, you will see that, with the right modifications, the 6.5L can comfortably “make the grade” and perform as a work truck should.

Duramax LML: More Power, Less Fuel

The 2011 Duramax LML replaces the LMM with More Horsepower and Torque While Adding More Than Ten Percent Fuel Efficiency

If you were looking to buy a new diesel truck and I told you that the Duramax brought additional horsepower to the table over last year's engine you might stop to consider it a worthy contender. If I told you that the table was shattered with 765 foot pounds of torque (up from 660 in last year's model) I'd get your attention. You might ask, extra horsepower and torque are great, but how much am I gonna pay for it at the fuel pump? As Joel Paynton pointed out before the new Duramax's release this Summer, the engine actually produces all that additional power while improving fuel efficiency and emissions. Now we learn from GM that the improved fuel economy may be as high as 11 percent. They also managed to make the EPA happy, or maybe just a little less unhappy, by reducing NOx emissions by at least 63 percent over the 2010 LMM.