[VernDiesel]

I had to edit this. I think it's great Ram now gives us a choice between 3.21 & 3.92. If there was only one gear split the middle and give us the 3.55. If it was for a car just the 3.21 would be fine.

What Bounty says is true but there can be discernment. At a max tow say its 8k the 3.21 has to divide the work IE accelerate the load up grades and on switchbacks transitioning the load speeds up & down and or maintain interstate speed especially into the wind with one less gear. Think carrying shingles up two ladders to the roof of a house. You are the engine and transmission. One ladder has 5 big steps one has 4 giant steps. The ladder steps represent the gears the 3.21 & 3.92 has available to use ie has enough torque or is strong enough to use when towing this load.

It's much harder and slower to carry the shingles to the top with 4 steps and more likely to have a joint or something give out. Now you are on the roof turn the corner you have 40 more ladders or switchbacks to do to get to the top roof or crest the mountain.

Are you picking 4 step ladders or 5 step ladders on your path to the top? If you are not carrying any shingles you might race four step ladders to the top. Ok now you are at the top. Which ladder path made you sweat the most or overhead first on the way up? Which ladder set made you use the most energy or fuel to get to the top? Don't set down the shingles you have to carry them back to the ground. Are you going to choose the 4 step or 5 step ladders to control your descent speed to the ground?

This represents one hill or mountain. Is there more than one mountain in the west?

Even with 3.55 vs 3.92 you can see where the 3.55 often tops out at 45 mph and the 3.92 at 50 mph towing heavy up a grade.

Is one gear set better than the other? Yes. If you don’t have to tow a high aerodynamic drag max load the 3.21 is better. Better highway mileage. With the exception being acceleration. The 3.92 truck will always be quicker. And well Ram generally rates the 3.92 to tow more than the same truck 3.21.

Back to the max load. Where the 3.21 truck would have to divide the work or acceleration with 5 gears and hold say 65 mph with 6 gear. The 3.92 would divide the work between 6 gears and be able to comfortably maintain 65 in the first overdrive or 7th gear.

Similarly only more exaggerated when the 2500 guys with the Hemi 6 speed had to do the above max tows they complained about the stuck high winding in a low gear to do the work. Because it didn’t have the smaller steps it needed to make and hold the next gear. When they transitioned into the eight speed with more gears to divide the work and better gear stepping the complaints stopped.

 

[VernDiesel]

Pretty expensive aftermarket upgrade both parts & labor for 4x4. Might be as cheap to trade trucks

 

[VernDiesel]

I modified an earlier post for first time readers but for the rest unless you look back you would never see it. So

At a max tow say its 8k the 3.21 has to divide the work IE accelerate the load up grades and on switchbacks up & down and or maintain interstate speed especially into the wind with one less gear.

Think carrying heavy shingles up two ladders to the roof of a house. One ladder has 5 big steps one has 4 giant steps. The ladder steps represent the gears the 3.21 & 3.92 has available to use ie has enough torque or is strong enough to use when towing this load.

It's much harder and slower to carry the shingles to the top with 4 steps. Now you are on the roof turn the corner you have 40 more ladders or switchbacks to do to get to the top roof or crest the mountain.

Are you picking 4 step ladders or 5 step ladders on your path to the top? 5 right because its easier and faster if you are carrying a heavy bundle of shingles. I mean If you are not carrying any shingles you might for speed choose the 4 step ladders to the top. Anyway now you are at the top. Which ladder path made you sweat the most or overhead first on the way up? The 4 step ladders right? Which ladder set made you use the most energy or fuel to get to the top? The 4 step ladders right? Don't set down the shingles you have to carry them back to the ground. Are you going to choose the 4 step or 5 step ladders to control your descent to the ground?

This represents one hill or mountain. The west if full of mountains.

Even with just 3.55 vs 3.92 we have often read on here over the years that 3.55 "holds the line" at 45 mph and the 3.92 at 50 mph.

 

[VernDiesel]

Sure it does.. with two sacks of groceries or less in the bed. Lol

 

[VernDiesel]

Accelerating a say 8k TT up switchbacks. Say you can effectively use and divide the work between 5 gears with the 3.92 to the speed you are able to attain. With the 3.21 you end up near the same final drive ratio and speed but get there slower and the motor works harder because it’s only able to do or divide the work between four gears. The 3.92 is going to do it more easily with more gears to use to accelerate and stay in its optimum rpm or torque range.

It’s like you are your same strength regardless of which latter you use to carry a 60 pound pack of shingles to the roof. Which are you going to be able to do it quicker and easier and with less stress on your body the latter with 5 steps or the one with 4 longer steps to the roof? Same principle.