2021 Ram 2500 6.4L (auto) gasser - what rear-end gears ratios are best for towing

[SNY SD UP]

If this is not the correct topic for this question, please let me know, and I will move it.

Wondering what those with a similar TV have as a R-E gear ratios.

Bryan

Thanks to all who will contribute useful knowledge,

[Steph and Dud B]

Our GMC 3500 gas (6.0) dually has the 4.10 rear end. The gas engine gets its best torque at higher RPMs than the diesels, which come with 3.73.

[John E Davies]

4.10 for sure,  but even that is not the best if you have oversized tires. The current Power Wagon comes with 4.10s and 33” tires (2010 and earlier have 4.56!). Tundras come with 4.30s and that would be a better choice for a Hemi for lots of towing. My Land Cruiser has 3.90 gears and 33” LT tires, and it struggles, the 5.7 Toyota engine has peak torque at 2800 rpm, and falls flat below that.

What are the ones in your truck? Are you thinking of changing them? That is a very expensive job with a very long payback, if any. I was quoted $4000 to install new Tundra gears.

Edit, the stock Ram 6.4 truck engine torque peaks at 4000, that seems really high for a work truck. An aftermarket chip to increase the mid-range power would help, but, I personally wouldn’t do that while under warranty.

John Davies

Spokane WA

[SNY SD UP]

35 minutes ago, John E Davies said:

4.10 for sure,  but even that is not the best if you have oversized tires. The current Power Wagon comes with 4.10s and 33” tires (2010 and earlier have 4.56!). Tundras come with 4.30s and that would be a better choice for a Hemi for lots of towing. My Land Cruiser has 3.90 gears and 33” LT tires, and it struggles, the 5.7 Toyota engine has peak torque at 2800 rpm, and falls flat below that.

What are the ones in your truck? Are you thinking of changing them? That is a very expensive job with a very long payback, if any. I was quoted $4000 to install new Tundra gears.

John Davies

Spokane WA

JD, thanks, if it runs that much, guess i will "run what you brung..."

i do not know yet. still reading owner's manual, just got the truck yesterday... i will look to see if it is on a sticker on the door or other visible frame.

[John E Davies]

I used to have a Ram, I don’t recall perfectly, but I think when you register your truck at the Ram owners website, you can view the window sticker and detailed specs for your truck. 

https://www.mopar.com/en-us/my-vehicle/dashboard/details.html

That 8 speed transmission has a really low first gear, almost 5:1, that will be great for getting the Ollie started from a stop. That won’t help going up highway grades, but it will be most excellent at low speeds. My LC200 6 speed in contrast has a 3.3 :1 ratio for first gear 😤

John Davies

Spokane WA

[GraniteStaters]

We have a 3.92 rear gear ratio in our 2019 Ram 1500 Longhorn Laramie with e-Torque option on a gas 5.7L engine.