Last post on Sep 27, 2013 at 11:50 AM
You are in the Chevrolet Silverado & GMC Sierra
What is this discussion about?
Chevrolet Silverado 2500HD, Chevrolet Silverado 3500, GMC Sierra 2500HD, GMC Sierra 3500, Diesel, Fuel Efficiency (MPG), Truck
#567 of 623 Re: Cold Air Intake problem [cbears85]
Dec 28, 2010 (10:54 am)
A gas engines computer system is even more complex than a diesels due to the emissions control system and the ignition system. Many, Many of the check engine light on situations with a gas engine are due to some component of the emissions system getting old and worn out. A computer code check should tell you what is wrong or at least what system is failing. Most common is EGR valves getting gummed up or Oxygen sensors that are in the exhaust manifold along with an EGT sensor getting literally burned out. Your truck is 7 model years old and was most likely built in late 03 to very early 04 so it most likely has enough miles to make these things a problem. You can replace them yourself if you get the correct diagnosis. Good luck
#568 of 623 Re: my take [hillsdale56]
Dec 28, 2010 (11:15 am)
Thank you very much for your input. Just some added information, my truck is not a diesel and does not have turbo. It has the 6.0L gas engine. Along with the Afe cold air intake, I also had dual Areo turbine mufflers installed. I don't know if that makes a difference or not. I guess I will need to get it on the computer to see what the error code is and then go from there. Also, I will try the mass air flow sensor cleaning and see what that does. Again, thanks for you input and time.
#569 of 623 Re: my take [cbears85]
Dec 28, 2010 (1:05 pm)
The guy who wrote post 558 was right on the money. I thought you ran diesel. The reason I said clean the mass air flow sensor is you said you cleaned and I presume reoiled the air filter a few times. The engine will pull oil into air intake, and coat the sensor. You said it went out sometimes. Try it see what happens. If not go get the dtc codes. Hope you find your trouble
#570 of 623 d-max mileage
Jan 07, 2011 (5:03 am)
To hillsdale56 , I responded on 1/4/11 but can't find my thread anywhere. So lets try this again. I havea '05 lly with 373's and line in the suburbs of chicago. 500' above sea level. I agree with filling the throte on the fuel tank to check mileage. always buy my fuel at the local Farm Service where the local school busses fill up. Did I understand you correctly to say that you can't run your truck in 6 lockup? Hope this thread gets to you.
#571 of 623 Re: d-max mileage [barrail]
Jan 07, 2011 (6:42 am)
Hey what's up? What you read is true. When diesel domination reprograms the ecm, it brings the max torque to 1900~ 2000 rpm. I have 373 also. My engine runs around. 63 mph. The engine runs stronger in fifth now. The easy tuner has a feature to monitor engine performance. That is sure way to tell. I have to have someone with me to watch the screen and see where the highest turbo boost is. I will post a thread when I do this
#572 of 623 Re: DURAMAX FUEL MILEAGE [gagrice]
Jan 20, 2011 (1:11 am)
I Have Solved my mileage problems on my 2008 duramax crew cab 4x4. I was getting 14.7 MPG . I did some research and found that in order for GM to meet the new emission standards they installed a particulate filter in the exhaust. This filter has fuel injected directly into the exhaust for it to work. This results in clean exhaust and poor fuel mileage. Now for the solution. I ordered a tuner the brand is H&S this tuner has a dpf ( Diesel Particulate Filter ) Delete which will allow you to replace the entire exhaust system from the turbo back and not set any codes in the ECM. I installed a new 4" exhaust and cold air intake system ( Banks ) . I could not believe the difference. The H&S system has 4 different power levels I rum on the hot or highest power level for best milage. I am now getting 20.2 MPG around town and 26.1 Mpg Highway.
I used to have the bully dog tuner on this truck with no milage improvement but good power but with these mods. This truck is pure mean I recomend everyone make these mods. It cost me about $1,200.00 for the tuner and exhaust. Well worth it especialy when I can out run just about any car or truck on the road.
#573 of 623 Re: DURAMAX FUEL MILEAGE [keygmc]
Jan 21, 2011 (10:43 am)
Glad to read about your good results. Right now I have a half a ton of wood in the back of my ride. With all the snow we are getting here in new york, I'll. Never get stuck. But its killing my city fuel economy. Stay warm
#574 of 623 Re: DURAMAX FUEL MILEAGE [keygmc]
Jan 27, 2011 (2:33 pm)
I'm real interested in the results you experienced with the H&S tuner. I to have a 2008 2500 duramax that averages around 14 mpg. Which exact set up did you purchase ? Whats involved with the installation? How many miles have you driven with the new tuner? Are you precise with your mileage estimates? What are you getting city and highway? Thanks for your response.
#575 of 623 $4.00 diesel fuel
Feb 10, 2011 (12:32 pm)
With this price just over the horizon again, like back in '08, I know that I can drive my '06 Duramax diesel for much better than the 18 mpg I have been accepting for quite awhile. All I have to do is slow down my acceleration after 30 mph and drive at 55 mph as much as I can. People have short memories but I can say that back in '06 to late '08 drivers of all kinds of vehicles did slow down and did save money. I would expect that driving 15 mph slower will result in a mileage increase of 6 to 7 mpg highway and 5 to 7 mpg city. This is all based on my '06 Duramax results over the last 5 years. I have always tried to drive for better mileage since fuel has rarely been below $3.00/ gallon since I have owned the truck.
#576 of 623 Re: DURAMAX FUEL MILEAGE [fueledup]
Feb 23, 2011 (6:04 am)
Hi, sorry it has taken me so long to get back to you. We are all feeling the pain at the pump. The mideast is in flames and oil has gone over 100 dollars a barrel. Know the name denise rich ? One of bill clintons inner circle. Her x husband marc rich is the one who put crude oil on the comodities market. The real reason I wanted to answer you is this. Remember my last post I said the wood I was driving around with for almost a month was killing my fuel economy?. Wasn't the wood. It was number 1 diesel. With this winter we have had. They have put a lot of kerosene in the fuel. When it hits 5 bucks a gallon, buy that time we will switch back too 2d . It was 8 degrees in upstate ny, last Sunday morning. What a winter!