LMM Fuel Economy

[mgscustomtune]

Here is a few pros and cons in the way mileage is calculated
When you calculate by hand you have no control over the temp factors,wind,grade to a given point which all effect the rolling stance of the truck. l recently did a calculation using a GPS and the on Board readings. I went 25miles constant speed 55mph pulling a 10,000lbs load the GPS and on Board Computer matched up exactly in distance with an average of 12.5mpg on the Computer. The next day which included some tempature change (5degrees higher) and wind(almost at zero) did the same trip. I got 13.5mpg. The on board PCM calculates the mpg including the wind/grade of road you are traviling on and temp change where calculated by hand you do not include those factors. I also took out a 2008 5.3 l was tuning at my shop drafted a transport on the HWY at 55mph l was amazed watching the onboard compter change from 22mpg not drafting to 25mpg when l drafted the the transport l think the onboard computer are a little moe acurate than we think. It is no secret that the New Exhaust Filter System hiders gas miliage and the amount you can strech the Custom Tune without a Delet of the System. Just my two pennys worth

[agmakar]

I own a 2006 Chevy 2500 HD Dduramax w/ 31,000 miles. I'm looking at buying the 2009 GMC 2500 HD. I'm not too comfortable buying the new deisels with all of the emmission mandates from the EPA thus having a reduced Fuel mileage than what I already have. I'm just getting 17 MPG in combined City and HWY driving mostly HWY, (54mi HWY, 13mi City).

What has been the AVG MPG in the new trucks now?

[christophersond]

I own a 2006 Chevy 2500 HD Dduramax w/ 31,000 miles. I'm looking at buying the 2009 GMC 2500 HD. I'm not too comfortable buying the new deisels with all of the emmission mandates from the EPA thus having a reduced Fuel mileage than what I already have. I'm just getting 17 MPG in combined City and HWY driving mostly HWY, (54mi HWY, 13mi City).

What has been the AVG MPG in the new trucks now?

I have a 2009 GMC Sierra, Crew Cab, 4WD, with just over 3100 miles on it. I haven't had an opportunity to check highway mileage yet, but in-town I am getting just over 14 MPG. As with the other Duramax trucks I've owned, I'm confident the MPG will increase as more miles are put on the truck.

[craigth]

I own a 2006 Chevy 2500 HD Dduramax w/ 31,000 miles. I'm looking at buying the 2009 GMC 2500 HD. I'm not too comfortable buying the new deisels with all of the emmission mandates from the EPA thus having a reduced Fuel mileage than what I already have. I'm just getting 17 MPG in combined City and HWY driving mostly HWY, (54mi HWY, 13mi City).

What has been the AVG MPG in the new trucks now?

Unless you have a very compelling reason to get a 2009 I'd keep your 2006. The new trucks are nice with the exception of the gas mileage. I had a 2002 that got 14-15 City and 15-19 Hwy. My 2008 gets 10-11 City and 14-16 Hwy.

The other thing to consider is that aftermarket chips/computers are not recommended as they will effect the new emissions equipment.

[agmakar]

There are no compelling reason other than getting a newer model with the added options and having a newer model before I retire. I like to research performance by asking others on thier experiences to get a better guage on what is going on with the new Truck inventories because the Manufactures and dealers will not tell the truth. I know fuel mileage ALWAYS takes a hit when new emmissions equipment are added I just did not know how much of a hit the new engines are taking. For me, fuel economy is first on my list when making truck purchase decisions.

Sometimes I think it's done on purpose to kill the deisel engine for other than commercial use.