- Sep 8, 2013
- Reaction score
- Ram Year
- 2024 1500 Limited Crew
- Hemi 5.7 eTorque
Actually with the increase of 8 and 10 speeds, you're getting less and less choice. Toyota only offers one gear, GM offers one I think unless you get the "tow package" etc.
The 3.21 with the 8 speed, has a deeper first gear than the old 6 speed used in the ram with a 3.92 or 4.10. Think about that.
In fact, the 3.21 with the 8 speed has a deeper first gear than the Tundra's 6 speed with 4.30 gears. It also manages to have a taller final gear than the Tundra, so not only can it pull harder off the line it will have lower rpms on the highway. Win win.
If you read the OP's comment, you'll see that his "problem" is on the highway. The 3.21 will give you pretty much identical final gear ratios as the 3.92 on the highway.
The difference between the gears (WRT towing) is only from a dead stop. But OP isn't complaining about getting moving, he's complaining about power and rpms on the highway, rear axle ratio won't change that in the slightest.
If you study the chart below then you'll see what we're talking about. The chart contains the calculated final gear ratios if both trucs are travelling at 65 mph. The 3.21 cells in orange "match" the 3.92 cells in orange. Same with blue colors etc.
Note how the 3.21 in 6th gear at 65 mph has 2191 rpms, which is identical to the 3.92 in 7th gear at 65 mph at 2194 rpms.
View attachment 523412
I've seen this several times before... those figures being equal, does not mean they are "equal" when it comes to stress on the driveline. There is a reason MFG's offer lower gearing and that equates to higher towing capacities. That's all I'm saying.
The OP also said he doesn't go over 65 mph - in the case of the 3.21, he would almost never be in 8th gear (or would be in-and-out of it constantly). So it absolutely has something to do with highway speeds - especially on 2-lane rolling hills.
I've driven my Dad's 2019 with the 3.21 a lot. It is nicer running 75+ on the interstate. Other than that, I much prefer the 3.92. AND, there's almost no difference in MPG's between our trucks unless we are racing up and down the interstate all the time. He's 84 years old and his MPG is virtually the same as my truck.
As for Toyota Tundra - If you watch some of the towing tests, they had issues with soaring transmission temperatures using that fast rear end (3.31 I think) even with the 10-speed.