Chevy 2004 6.0 vs. 2015 6.0

My new one has 4.10 gear. Had a 2011 before this with no clue what axle ratio and this one does a bit better than it did but it also had 100k mi on it. The new one is getting 13-13 1/2 mpg empty at 75 and last week pulling the 12k it was 6 1/2 - 7 mpg. The average over the 5000 plus mi on it so far is 11.3

TomG2 wrote:
I had a 2007 and now have a 2013 Silverado 6.0. Don't expect a huge improvement in power, or fuel mileage for that matter.

I have to disagree...but it might just by my experience. What is the weight of your trailer? I tow a trailer that is about 6200-6400 axle weight and 800-1000# tongue weight ready to camp.

We towed with a 2004 3/4 Ton Suburban with the 6.0L/4 speed and 3.73 axle. It couldn't maintain speed in 4th (OD) on level ground so I always used 3rd while towing. In daily driving my wife got 12mpg and we were lucky if she got 13mpg.

I now tow with a 2011 Express 1 ton, 6.0L/6 speed and 3.42 axle. I am able to tow in 5th gear on level ground and even overpasses and small grades. Larger grades it uses 4th gear. In daily driving my wife gets 15mpg. We do get about the same gas mileage towing.

I would think that you are going to have a nice improvement. Are you staying with the 4.10 or getting the 3.73? On steep grades are you going to have to let it rev? Yeah, but I love the combination I have.

You're going from 300hp/360tq and a 4 speed auto to 360hp/380tq and a 6 speed auto.

You're also getting a new chassis and a much better interior.

That said, it's still a gas engine with no turbo, and will use higher RPM to climb grades. No biggie.

I had a 2007 and now have a 2013 Silverado 6.0. Don't expect a huge improvement in power, or fuel mileage for that matter. The six speed is a big improvement and will help you keep the engine in a good power band. Small engine, lots of rpm's.

Those high RPMs just scare me. I wish I could afford the diesel

Bruce

I have a 2015 for a work truck, as long as the rpm' s are up it will pull a hill ok. Had about 12k behind it last week and tach was at 5500 for along time but it got the job done.

I'm going to say it will do noticeably better but you will still have to get the RPMs up on some of the grades. You will also be gaining two more gears going from an '04 to a '15. Congrats on the new truck by the way. :)