Which setup for best MPG on the Hemi

[Willyq711]

Hey all,

Looking at two preowned non-etorque Hemi's, both 2019's (Longhorns). I'm looking to get some feedback on which of these will give better gas mileage....

1. 2019 Longhorn, Hemi non-etorque, 2x4 with 3.92 axle.

2. 2019 Longhorn, Hemi non-etorque, 4x4 with 3.21 axle.

Most of my driving is 50/50 city/hwy and very little towing, if any. I do drive spirited at around 80+ on the Hwy.

The question here bis what's more beneficial for fuel economy... The weight savinga and lesser drive train work of the 2x4, or the lower gear ratio?

Thanks.

 

[vincentw56]

Hey all,

Looking at two preowned non-etorque Hemi's, both 2019's (Longhorns). I'm looking to get some feedback on which of these will give better gas mileage....

1. 2019 Longhorn, Hemi non-etorque, 2x4 with 3.92 axle.

2. 2019 Longhorn, Hemi non-etorque, 4x4 with 3.21 axle.

Most of my driving is 50/50 city/hwy and very little towing, if any. I do drive spirited at around 80+ on the Hwy.

The question here bis what's more beneficial for fuel economy... The weight savinga and lesser drive train work of the 2x4, or the lower gear ratio?

Thanks.

2x4s are for wood. 4x2s is for trucks.

Number 2 would probably give the best. But keep in mind you are probably only going to see a 1 or 2 MPH difference.

 

[beetlespin]

I have number 2 and regularly see 20-22 mpg.

 

[irishwake63]

if ya want a good 4x4 get a Jeep if ya want a gas efficient vehicle get a Prius if ya want a truck that will tow more get the 2X4 3:92

 

[Scram1500]

If you travel at 80+ the 3.21 will get the better mileage even with 4x4. That said the 3.92 2x4 would be a blast, unless it doesn't have limited slip then you could be gimped by wet grass

 

[Richard320]

I would guess it's gonna be a tossup.

I have 4x4 3.21. It's what I wanted because I anticipate moving somewhere with 80 mph speed limits once the wife retires. However, sometimes I get to drive that fast locally, and the truck will downshift on a 4% grade when I'm going 75-80. There's a post here that explains the math. 7th gear w/3.21 is the same RPM as 3.92 in 8th. So I haven't gained anything with the 3.21.

Your 50% city driving will benefit from the lower gears, because 3 tons is a lot of weight to get moving.

Where I have seen great fuel economy is on long drives on two lane highways or where the road is really flat. Then it's easy to get 21-22 mpg, so long as you keep the speed below 70.