I am now driving a 2013 Silverado 2500 HD. It has a 3.73 rear end and I like the mileage as well as towing power with my Z20 hooked up. A 1500 is not an option and Chevy doesn't offer the 3.73 in a 2500.

It has been a long time since I had this rear end. It was a gas guzzler. What I need to know is have they made any changes that allow better mileage?

I don't think it's enough to just look at the rear end. You also need to factor in tire radius and transmission ratios to determine a final drive ratio.

5 Years of improved engine design and two extra transmission gears are a couple things but we really need to know what engine and transmission you have in your 2013. As Samsonworld said it's not enough to just look at the rear end ratio.

A 2013 2500 hd gas is going to have a 6-speed auto. What kind of mileage do you get out of it with 3.73's?

Pretty sure the new ones have the same transmission. 4.10's will give you a little less fuel economy and more umph, but I don't think the rear end change will be a huge impact on fuel economy.

I'm sorry for the lack of info. 6 liter motor and 6 speed automatic. I can get 17 interstate driving, 12-13 towing the boat, 12-13 around town and 8-9 pulling the 5th wheel.

I'm assuming to get those economy numbers you don't just put the hammer down and drive with fuel mileage in mind at something probably less than the posted limit. I bet you take a hit of 1-2 mpg going to a 4.10. We had a 6.0 with 4.10 gears and it got about 14-15 with the old 4 speed transmission, I'm sure the 6-speed will help it out a little.

That said most people will call you a liar for claiming what you get, but ive done and seen similar. If you drive them right they will surprise you.

Thanks for the reply. I always drive with mileage in mind. I haven't been in a hurry to get anywhere for a very long time. I have been looking all over the place for a red 2500 with the 3.73 but can't find one anywhere.

The 4.10 ratio is an option. That�s why your having problems finding one. Open the glove box and on the sticker on the inside of the glove box door, look for GT5. That is the RPO code for the rear axle final drive ratio of 4.10:1

2013 Silverado 2500HD, 6.0, 4.10 gears, Ranch Hand bumpers. leveled with BFG All-Terrains. I get 12mpg average and 10 with the boat.

If you want mpg stay away from 4.10! 3.73 is what most diesels run because of torque produced from the diesel engine. I have owned several trucks with varius engine displacements in 4.10 and 4.11 you will not see more then 13mpg average and less towing depending on load.