Hello all, new to site, just bought a 09 Ram Sport 5.7 with 3.55 gear, thing pulls like crazy, had 01 Chevy with 5.3 and 4.10 and this truck feels so much stronger. I can't even imagine what it would be like with the 3.92, how much seat of the pants feel would there be, just wondering. thanks

 

Seat of the pants during normal driving won't be extraordinarily different, due to the VCT which makes the engine much more driveable in the low end range. Towing though is where you'll notice the difference, as with the 3.92s, you are asking the engine to pull less gear for the same speed.

On my '05, I went from 3.92s to 4.56s and unloaded, the truck actually felt a little more sporty with the 3.92s, as the engine has enough nut to pull the bigger gear unloaded. Towing though, there is a huge difference in driveability with the higher gearing. "Don't fear the gear..."

 

The biggest difference between the two is that the 3.92 is a limited slip and the 3.55 is an open diff. With the traction control, it is not a huge thing, but the open diff uses the TC much more often. You don't feel a huge difference in acceleration, but you do feel it. I tell people to drive a 3.21 and then a 3.92 if they want to see if the diff makes a difference.

The 3.92 raises the RPMs on the highway about 200 more which IMO gets the Hemi into a smoother area range. The 3.92 will get about the same highway mileage, but better in the city. I have a sport with the 3.55 and would have got the 3.92 or even 4.10s, but I got a great deal on a demo.

 

You will need the 3.92 with the taller 20" wheels.

 

Smart guy here. It is the final ratio that really matters. The taller the tires get you want bigger gears to keep the same final ratio.