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3.21 vs 3.92: The Last Word

c3k

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I am comfortable in my masculinity and feel no need to try to prove myself to strangers, hence the 3.21. (But I did paint "3.92" on my diff cover because my wife's sister laughed at me at the last reunion. So, there's that....)

;) :) :)
 

djevox

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I am comfortable in my masculinity and feel no need to try to prove myself to strangers, hence the 3.21. (But I did paint "3.92" on my diff cover because my wife's sister laughed at me at the last reunion. So, there's that....)

;) :) :)
I got giant eggplant stickers for the fenders to make up for my tiny gears
 

Ninety-9 SE-L

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It's not apples to oranges. We're talking about exceeding the capabilities of a vehicle. I'm just willing to go a little further when I ignore the limitations. Your truck has a rated towing capacity for a reason, whether you agree with it or not. It's not "just because," it's because your truck is less capable than my truck. So is a midsize SUV. So is a minivan.
It's Apples to oranges when you change every single factor, including the type of vehicle. If we're simply comparing 2 identical trucks with a different final drive there is some discussion to be had.

I do understand the tow capacity is issued for a reason, and I'm usually very strict about codes. However, I also understand that those capacity codes are also a catch-all for all regions and all morons driving at any somewhat legal speed. I don't believe that the religious faith (on this forum) to the 3.92 should steer people away from the 3.21, even if those people tow. How often you tow, how much you tow, and under what conditions you tow are still very big factors.

I'm not advocating people with lower tow capacities straight up ignore their tow ratings and hit the Rockies with a 33ft Airstream on their tail, but take your tow ratings with a grain of salt. Proper weight distribution, route planning, and self-control are still more important factors.

I like to use this image from time to time, because in the US, it's not that we like to tow a lot of weight, it's that we expect to tow all that weight at 80mph on the freeway without trailer brakes, regardless of the region.
z3MJkrI.jpg


A mechanical advantage means less power is needed to accomplish the same work.
The 3rd Gen EcoDiesel produces 240hp and 480lb-ft of torque. Depending on Transmission losses, that's about how much comes out of the Transmission's butt hole. Not a penny more. A mechanical advantage or disadvantage can also simply mean that less "work" is done.

Also, you're confusing work with torque. What's interesting is that the work/power is the same. You're displacing torque for rotational speed.

MORE work is not being done, so you're confusing the idea that there is more strain in the transmission. And as mentioned, our transmissions are built to handle the strain of a 4x4.
I have the stock tires on my truck, and would only change them for the exact size with a better load rating.
If you have to keep adding qualifiers on top of qualifiers to make the 3.21s seem better than they are...well, is that really what you're doing?
Again, I'm making a point that this forum considers the 3.21 to be inferior crap and not 'recommended for towing', yet they have no problem stacking on their own mechanical disadvantages with 4WD and big mud tires.

I guess I could make the argument that if you PLAN on buying a 4x4 and upgrading your tire diameter, then you probably should get the 3.92, because you're just stacking on that mechanical disadvantage.

OK, but if you can exceed DOT tow ratings, so could someone with 3.92s. And you're exactly where you started.
The 2022 Ram 1500 can tow up to 12,750lbs. If I took my 3.21, threw 12,750lbs (4500lbs over) on my back bumper, I'd still be able to handle and stop from 70mph. My truck wouldn't be too happy getting to 70mph, but my chassis is built to handle that kind of load.....I'm not saying that's safe, I'm simply making a point about the overall package.

If someone with a the max configuration put 17,300lbs (also 4500lbs over) on their back bumper, they'd probably need new tires and shocks. Assuming they dared get to 70mph, they would not be stopping at any safe distance or descending any hills.

I don't remember the last time I saw a thread that was started for any reason other than to explain away why 3.21s aren't mostly useless after all, including the one you're in now. They aren't trash, but you do have a better option if you didn't just buy whatever you could find on the lot.
Perhaps because others have chimed in.

I mean, look, I bought a 3.21. I'm not just blindly attempting to defend my purchase. I tow a few dozen times a year, often not great distances, often not over 8,000lbs. I can fully assure you that I will not be exceeding my tow capacity more than a few times in the next 5 years and almost certainly not at highway speeds or hilly roads. It's disappointing that more people, including enthusiasts, don't get the 3.21 configuration, because there seems to be some agreement that the 3.21 is egregiously slow or incapable of pulling weight.

Overall, I think the DT is good for 10,000lbs, for MOST people in MOST situations, regardless of what configuration you have, and I'm basing that off of the chassis more than the drivetrain. Results may vary depending on where you want to take that 10,000lbs.
 

SnowBlaZR2

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It's Apples to oranges when you change every single factor, including the type of vehicle. If we're simply comparing 2 identical trucks with a different final drive there is some discussion to be had.
Once again...if you're going to compare two different vehicles and pretend that they perform the same, then so can I. Your truck and my truck are different. My truck and a minivan are different. You're just talking about how different they are now. Your truck and a minivan are both less capable than my truck, but hey, you probably have the minivan beat. 😉
I do understand the tow capacity is issued for a reason, and I'm usually very strict about codes. However, I also understand that those capacity codes are also a catch-all for all regions and all morons driving at any somewhat legal speed. I don't believe that the religious faith (on this forum) to the 3.92 should steer people away from the 3.21, even if those people tow. How often you tow, how much you tow, and under what conditions you tow are still very big factors.

I'm not advocating people with lower tow capacities straight up ignore their tow ratings and hit the Rockies with a 33ft Airstream on their tail, but take your tow ratings with a grain of salt. Proper weight distribution, route planning, and self-control are still more important factors.
Tow whatever you want. We're talking about capability here. Just because you're willing to exceed the capability of your truck doesn't mean it's actually just as capable.
The 3rd Gen EcoDiesel produces 240hp and 480lb-ft of torque. Depending on Transmission losses, that's about how much comes out of the Transmission's butt hole. Not a penny more. A mechanical advantage or disadvantage can also simply mean that less "work" is done.

Also, you're confusing work with torque. What's interesting is that the work/power is the same. You're displacing torque for rotational speed.

MORE work is not being done, so you're confusing the idea that there is more strain in the transmission. And as mentioned, our transmissions are built to handle the strain of a 4x4.
Are you talking about equations?

I'm using normal words because we're having a normal conversation.
Again, I'm making a point that this forum considers the 3.21 to be inferior crap and not 'recommended for towing', yet they have no problem stacking on their own mechanical disadvantages with 4WD and big mud tires.

I guess I could make the argument that if you PLAN on buying a 4x4 and upgrading your tire diameter, then you probably should get the 3.92, because you're just stacking on that mechanical disadvantage.
This would also require the assumption that no one with 3.21s puts bigger tires on their trucks. That isn't the case, of course.

Regardless, as I said, I'll be keeping the stock tire size so this point is entirely meaningless to me.
The 2022 Ram 1500 can tow up to 12,750lbs. If I took my 3.21, threw 12,750lbs (4500lbs over) on my back bumper, I'd still be able to handle and stop from 70mph. My truck wouldn't be too happy getting to 70mph, but my chassis is built to handle that kind of load.....I'm not saying that's safe, I'm simply making a point about the overall package.

If someone with a the max configuration put 17,300lbs (also 4500lbs over) on their back bumper, they'd probably need new tires and shocks. Assuming they dared get to 70mph, they would not be stopping at any safe distance or descending any hills.
:LOL:

Of course it wouldn't be happy. That's...kind of the point.
Perhaps because others have chimed in.

I mean, look, I bought a 3.21. I'm not just blindly attempting to defend my purchase. I tow a few dozen times a year, often not great distances, often not over 8,000lbs. I can fully assure you that I will not be exceeding my tow capacity more than a few times in the next 5 years and almost certainly not at highway speeds or hilly roads. It's disappointing that more people, including enthusiasts, don't get the 3.21 configuration, because there seems to be some agreement that the 3.21 is egregiously slow or incapable of pulling weight.

Overall, I think the DT is good for 10,000lbs, for MOST people in MOST situations, regardless of what configuration you have, and I'm basing that off of the chassis more than the drivetrain. Results may vary depending on where you want to take that 10,000lbs.
Right...which is exactly what most will tell you. If you hardly use your truck for much more than commuting, get whatever you want. But don't expect us to play pretend with you when you act like your truck is just as capable. It isn't, and there's simply no way to explain that away.
 
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theblet

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3.92s wont make an engine produce more power or torque, it means the drive shaft turns 3.92 times to the axle turning 1 time, hence the higher RPM. This means your engine will have the max available torque sooner than 3.21 gears, but sacrifice some mpg.
 

theblet

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Once again...if you're going to compare two different vehicles and pretend that they perform the same, then so can I. Your truck and my truck are different. My truck and a minivan are different. You're just talking about how different they are now. Your truck and a minivan are both less capable than my truck, but hey, you probably have the minivan beat. 😉

Tow whatever you want. We're talking about capability here. Just because you're willing to exceed the capability of your truck doesn't mean it's actually just as capable.

Are you talking about equations?

I'm using normal words because we're having a normal conversation.

This would also require the assumption that no one with 3.21s puts bigger tires on their trucks. That isn't the case, of course.

Regardless, as I said, I'll be keeping the stock tire size so this point is entirely meaningless to me.

:LOL:

Of course it wouldn't be happy. That's...kind of the point.

Right...which is exactly what most will tell you. If you hardly use your truck for much more than commuting, get whatever you want. But don't expect us to play pretend with you when you act like your truck is just as capable. It isn't, and there's simply no way to explain that away.
depends on what capability you're referring to :p
 

Mountain Whiskey

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It’s clearly more capable to go longer distances between fuel stations!


Sent from my iPhone using Tapatalk

Well, if you are going downhill with a tailwind and no payload on stock Prius tires, then yes, you may get an extra 5 miles or so from a tankfull.

I should have been more specific. Most CUV/SUVs can handle about 5k. Our trucks can handle 9-10k, on average. The main reason for that is our frame, tires, brakes, length/width, power, and gearing. Sure, an SUV could handle some small campers, but nothing major and certainly not to our trucks' limits. Apples to oranges. The 3.21/3.92 argument isn't even close to comparing a 1500 to a midsize SUV. Trust me, I tried looking before I settled on another pickup truck.

For powertrain strain, the 3.92 has a higher reduction to produce more wheel torque. It's easy to think that because there's a smaller multiplier than more torque has to come off of the AT's output shaft to produce the same power. That's not exactly true. I can't make the engine/transmission produce more or less power/torque just by changing the rear end. I'm simply giving myself a mechanical advantage at the wheels. At 100% throttle, the transmission is going to output the same amount of power/torque regardless of what's down the line. At continuous cruising speed, I may have more torque coming off the transmission in order to make up for the 15-20% loss in rear-wheel torque, but that doesn't concern me because I'll only be operating at partial throttle.

It also doesn't concern me because I have RWD and no plans to **** with the wheels/power train. A lot of ya'll own 4x4s and have increased your tire diameters. Are you guys having problems with the A/T, heat, or reliability? Didn't think so. Putting on bigger diameter tires reverses some of the advantage in the 3.92. Transfer case, 2 prop shafts, 2 diffs, 4 axle shafts, hmmm, that could put more strain and drivetrain loss on your transmission. That sounds a lot harder on your powertrain than simply having a longer(shorter?) final drive.

I'm not claiming to know better than the Engineers that rate our trucks, but I know that many of these DOT tow ratings exist in order to weed out the least common denominator, like this guy:
View attachment 129646

If I was making a lot of pulls up mountain passes or I needed a lower crawling gear, I'd definitely think twice about having a 3.21. But I think a lot of you put way too much praise into the 3.92, and maybe it's because a lot of you do things that require a crawling gear, or it's because most of you have 4x4s and large-diameter tires that adversely affect your acceleration.

I've only been on here a short while, but I can see this discussion comes up a lot. Ya'll really put way too much belief into the 3.92 while passing the 3.21 off as trash. Especially when you can drop down a gear and basically have all the same final drive ratios (except 1 and 8). The 3.21 has its limits, but honestly, I wouldn't think twice about putting 10k on the back of my truck in all but the most strenuous circumstances, which will probably never be a problem because I don't live in the mountains.
So you are saying 3.21 gears suck. Got it!
 

BigD

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I had a 2013 Ram with the 6 speed tranny & 3.21 gears. Now I got a 2020 Ram with 8 speed tranny & 3.92 gears. Man, what a difference!! Like night & day. Lots of fun to drive.
 

theblet

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I had a 2013 Ram with the 6 speed tranny & 3.21 gears. Now I got a 2020 Ram with 8 speed tranny & 3.92 gears. Man, what a difference!! Like night & day. Lots of fun to drive.
Passes up everything but the gas station 😆
 

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