Egine RPMs at 70 MPH

[Bcsvil]

I wanted to get an idea on the difference of engine rpms while cruising on flat terrain while not trailering a load. For example I have a new 2020 ram bighorn 5.7 3.92 18" wheels and average around 1900 rpm at 70 mph. I just wanted to get an idea in the difference between powertrain options.

 

[crash68]

The 18" and 20" OEM rim/tire size are both 32" so at 70 mph in 8th gear:
3.92 = 1850
3.55 = 1650
3.21 = ̶1̶5̶5̶0̶ *1500

 

[Bcsvil]

The 18" and 20" OEM rim/tire size are both 32" so at 70 mph in 8th gear:
3.92 = 1850
3.55 = 1650
3.21 = 1550

Thanks I appreciate the info! I really wish they would have allowed the option of the 3.55 with the 5.7 L. I wonder why they don't?

 

[crash68]

There is not much difference gear multiplication wise between 3.21 and 3.55 for the available HP/torque with the Hemi.

 

[Firebird]

I turn 1900 at 70

 

[John Jensen]

I have 3.55 and run 1770 @ 70mph with 33" Falken Wildpeak A/T3W 10 ply -632 rpm (OEM 634 rpm)

 

[dgibson]

I live in the hills. I had a 2014 limited with 3:21. Constant backshifting on hills. Now the new one 2019 Laramie longhorn, no e-torgue is less back shifting.