6.0L gas RE vs mpg
Anyone guess or estimate the MPG improvement between 4:10 and 3:73 in the new gas GM trucks? How would we determine the mpg improvement switching out from a 4:10 to a 3:73 ... Got about 1100 m...
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APT wrote:
Does 1100 miles on this 6.0L mean it is a new 2014 model with 4.10 axle?
My 6.0L broke in and reduced fuel consumption after about 20k miles. I bought in October, got 11-12mpg all winter. This winter which is far colder is netting 13mpg. Towing the first summer was about 7mpg. Second summer was 8mpg. We have done a few 1000+ mile non towing trips from 6500 miles on the odo to 38k and have had up to 18mpg. So I think yours will improve somewhat.
2015 GM 2500HD Dbl Cab, not 2014, yes, new two weeks ago. It shows around 15-16 on the highway empty first 500 miles, and when I popped the TC and hit the highway again - it slowly dropped (Of course, carrying 3200 lbs now) it went to 10.5 mpg -- so, it runs great and hauls great, but I was a little disappointed in the mpg. I'd hoped to haul at about 12 mpg at least. My 2003 and 3:73 hauled TC weight at 11-12 mpg. Even with the 4:10, I'd expect with the new tech stuff at least equal to the old 6.0L and 3:73 ...
SO, hopefully it will improve. One other thing too -- after about a week, the start began sound weird - instead of kicking right over, it winds a bit, numerous revolutions, and coughs, then starts. Not every time, but maybe 20% of the starts.
Actually sounds like fuel issue or a spark issue, so that might help as well. Will give it another 1000 miles, then take it in -- or maybe sooner if this 'cough/start' keeps at it. Does it more often in cold-damp weather. As if moisture is impeding the spark, although have no clue how moisture would get inside anything ...
