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About unit

  • Birthday April 19

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  • Name
  • Location
    Springfield, Ohio
  • Gender
  • Interests
    cars, bicycles, traveling
  • Drives
    2020 Silverado 2500HD Crew Cab, Duramax/Allison

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  1. Diesel fuel isn't the only expense with the Duramax. You have to figure in cost of DEF on any diesel and that does add to the expense calculations. Newer diesels tend to use a lot of DEF while towing and it's about $4.00 / gal at the pump.
  2. I had mine done on June 1st and I haven't noticed any difference in mileage or drivability. I towed my 8,000 lb Airstream trailer 300 miles on Tuesday and will be returning home tomorrow. Towing was normal and I averaged 14 mpg on the outbound trip. I expect the see a regen on tomorrow's return trip and we'll see how that goes.
  3. I've towed my 30' Airstream to the west coast and back from Ohio, 6,500 miles total, and averaged 13.4 mpg. That's legitimate hand calculated mileage. The trailer weights about 8,400 lbs loaded. I have a Banks iDash and it displays the active gear, which is the only way I know with a GMC or Sierra to tell the gear. It seems counter intuitive but I find I get the best mileage when the truck is in 10th gear. At 60 or 62 in tow/haul mode the truck stays in 9th gear most of the time. If I speed up to 68 or 69 the truck will shift to 10th and mileage goes up a smidge. Normally, I would swear that you'd always get better mileage at a lower speed but this truck is different than others I've had. I can only attribute it to the 10 speed transmission with it's three overdrive gears. Fords and Rams will display the trans gear on the dash - not sure why GM doesn't. It's really nice to know what gear the truck is in at any given time. This is my experience and others will have different results. Wind speed, wind direction, altitude as well as the weather are also factors that can affect mileage in different ways. Size, weight and shape of the trailer also play a huge part in fuel mileage.
  4. I simply raise the hood after washing the truck and let any water trapped under the hood furniture drain away. Put the hood down after drying the truck and the problem is solved. You won't have a problem with water running out later or spraying out in a mist driving the first few miles after the wash.
  5. To answer the question posed by 'sheath'; yes I do all of the things in my prior post. I can easily gain 2 mpg over the mileage I get when I ignore those practices. I'm not a super conservative driver but I like to conserve fuel when I can. It's not hard and I can use money saved for other things.
  6. You can increase fuel economy by: 1. Slowing down, cruising at 60 will get better mileage than 70. 2. Maintain a steady speed, use cruise control when possible. 3. Avoid idling - it wastes fuel. 4. Keep tires inflated to recommended pressure.
  7. We can't find people who will work here now, how do you suppose we'll find that many more workers if some of jobs were to return to the US?
  8. If memory serves me, the fuses on the passenger side are hot only when the ignition is on. The driver side fuses are always hot. Not sure where your problem lies but hopefully this helps.
  9. I got the truck back today from the dealer. The truck was throwing a P122D code, which is a throttle valve position error. Testing showed the valve did not return to the closed position when the engine was shut down. The throttle body was replaced and that resolved the issue. Seems unlikely but it's good so far.
  10. My grandson is in the US Army and stationed at Joint Base Louis-McChord. He has a 2008 Silverado 2500HD with the Duramax engine with approximately 110,000 miles. He's been getting a P2563, VGT Positon Sensor, CEL code on and off for the last 10K miles. He has no place to work on the truck and really no experience working on diesels so we're looking for a competent diesel repair shop in the JBLM - Tacoma area to do the repair. We'd appreciate any recommendations to a good shop.
  11. My truck is showing the same message this afternoon. I have an appointment with the dealer tomorrow to have it looked at.
  12. Do you have anything plugged into the ODBII port under the dash? If you do, then unplug the device from the ODBII port and try again. That will sometimes make a difference.
  13. I'd like to have Super Cruise and I'd be tempted to make the deal, but Idaho is a little further than I want to go to pick up a truck. I'm also waiting to order the truck with everything working from the factory. I'm not fond of buying a decontented truck that may get the features restored at some future date. That's just my take on it.
  14. It could be the pigtail on the trailer. My 2020 2500HD did not like the pigtail on my 2018 Airstream trailer. I changed the pigtail to one with blade type connectors and it solved the problem. The new pigtail slides into the truck plug easier and makes a more secure connection. This might not fix your problem but it's inexpensive and worth a try. https://www.amazon.com/NEW-SUN-Connector-Trailer-Adapter/dp/B07HVS1SY3/ref=sr_1_14_sspa?keywords=trailer+pigtail&qid=1642040293&sprefix=trailer+pig%2Caps%2C97&sr=8-14-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExWkgwR1AzMEhXR0tSJmVuY3J5cHRlZElkPUEwMTc4Njg5MVVaU1g2NTZCVERFTSZlbmNyeXB0ZWRBZElkPUEwODU2MzkxM09XWTdKVDFCSklJQSZ3aWRnZXROYW1lPXNwX210ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
  15. If you get it wet and keep it wet, it will soften up. You'll need to remove the wheel well liner to gain access to the down pipe and anything else that needs cleaning. Once the mud is softened, you can scrub it with a stiff brush to remove the heavy stuff. I wouldn't use a wire brush because there are wires in the area. A household spray cleaner should work well on any residue once the thick stuff is gone. Best of luck with it.
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