Difference between 3.21 and 3.92 Axle Ratios

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TRCM

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Laws were made to be broken.
I'll brake the laws I want, you act like ol mr. high and mighty all you want.


Wow....and from someone over 25 yrs old.

Well, I'll tell ya what...if following the law and not feeling like they just don't apply to me is being high & mighty.....then guilty as charged.

Thankfully, the world isn't completely full of selfish people who feel laws don't apply to them....yet.
 

yillbs

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Wow....and from someone over 25 yrs old.

Well, I'll tell ya what...if following the law and not feeling like they just don't apply to me is being high & mighty.....then guilty as charged.

Thankfully, the world isn't completely full of selfish people who feel laws don't apply to them....yet.

As long as they keep reproducing, we'll get stuck with loads of 'em. :word:

To actually.. answer the quesiton now. Yes, it's a big difference, the capacity is altered, but I don't think i'd want to tow 10k with a 1500 anyways. I like to keep it about 1k under what it's rated. I have a 6 inch lift, and 35" tires with 3.21 gears, I've towed with it once, ( only a week or so old ), and it didn't break a sweat. you're going to notice larger loads have issues on the hills, just put it in a lower gear and drive it like it needs to be driven.

the 3.21 is the sweet spot for gas mileage on these things, nothing more. Aside from poor gas mileage, and some manual intervention with larger loads, the 3.21 is capable, the power isn't any more reduced on the freeway than any other truck. contrary to what everyone seems to say, you WILL feel it behind you :p
 

JLEONARD

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Don't buy that specific truck for pulling 8k lbs around. You have to look at your max payload on the sticker inside the door. Tongue weight+ weight of everyone and everything in and on the truck that didn't come from the factory, Im going to guess your right at or above your max payload.
That combined with 3.21 rear end is not going to be fun. This is the exact reason I just traded my 1500 in for a 14 Ram 2500, and I had 3.92s in there with aftermarket airbags in the rear. You can't change the payload unfortunately.
 

14RAM4X4

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^^ I traded my 2014 1500 4x4 for a 2015 2500 4x4. I only had 3.21s and it was not fun trying to pull my little 24' TT. Sure it pulled it great on flat roads/hwy. Stopping was ok. BUT, I then I pulled it through the Texas Hill Country.... That was a white knuckle ride to and from. Up & down hills with turns and bumps/humps in the roads..... I'm sure a weight distribution hitch would have made a difference, but the rear end of the truck was bouncing up & down and swaying too.

The same trip in the 2500 is a completely different feeling. No WDH and the rear of the truck still feels firm and steady. It was worth it to me.
 

yillbs

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^^ I traded my 2014 1500 4x4 for a 2015 2500 4x4. I only had 3.21s and it was not fun trying to pull my little 24' TT. Sure it pulled it great on flat roads/hwy. Stopping was ok. BUT, I then I pulled it through the Texas Hill Country.... That was a white knuckle ride to and from. Up & down hills with turns and bumps/humps in the roads..... I'm sure a weight distribution hitch would have made a difference, but the rear end of the truck was bouncing up & down and swaying too.

The same trip in the 2500 is a completely different feeling. No WDH and the rear of the truck still feels firm and steady. It was worth it to me.

The 3.21 gear ration wouldn't have made the swaying any different... Moreover, the POWER to pull the trailer up the hills here in texas won't be affected either. The GAS Mileage will.. but the actual ability to TOW the trailer behind you isn't altered. I'm worried when people ask questions like this, they use google 2 years from now, and find threads lke this. It's extremely important to understand the importance of a gear ratio. If the truck is capable of towing 8k at max payload ( example number here ), then that's what you can tow / haul. Having the smaller gears doesn't give you a truck with a smaller motor, you still have the same transmission, and you still have the hemi beast under the hood.

If you're okay with better gas mileage, and a lower max payload, the 3.21 isn't a bad thing. I only bring this up because your choice in saying " I only had " , as if it were somehow preventing you from towing what you had.
 

14RAM4X4

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The 3.21 gear ration wouldn't have made the swaying any different... Moreover, the POWER to pull the trailer up the hills here in texas won't be affected either. The GAS Mileage will.. but the actual ability to TOW the trailer behind you isn't altered. I'm worried when people ask questions like this, they use google 2 years from now, and find threads lke this. It's extremely important to understand the importance of a gear ratio. If the truck is capable of towing 8k at max payload ( example number here ), then that's what you can tow / haul. Having the smaller gears doesn't give you a truck with a smaller motor, you still have the same transmission, and you still have the hemi beast under the hood.

If you're okay with better gas mileage, and a lower max payload, the 3.21 isn't a bad thing. I only bring this up because your choice in saying " I only had " , as if it were somehow preventing you from towing what you had.

Maybe I should have clarified that I also had tires taller and wider than stock (295/60r20s - 34"). The 3.21s didn't limit my ability to pull the trailer. They definitely didn't do anything to improve the towing, that's for sure. After the lift and tires, the truck already felt sluggish compared to stock. From a dead stop, it pulled great thanks to the 8 spd. But once I got up to about 4th, the trans seemed like it was always searching for the right gear. Like I said in my post, it pulled fine on flat roads (like driving down to the coast).

When I talked about towing in the hill country, it was the suspension, not the gears that I talk about, althought again, the gearing did play a factor. Some of those roads up there are 60 mph and the slower ones are still 50 mph. I never did 60 mph, and even felt uncomfortable at 50 mph on most of those roads. Again, though, the transmission always seemed like it was searching for the right gear. Having 3.92s would have given the engine a few more rpm in the powerband to hold gear better.

Right now the 3.73s with my 295/65r20s (35.4") and six speed is too tall. That big 6.4 Hemi feels sluggish without the trailer behind it. More so with the trailer. BUT man, I love the stock trailer brake on my 2500. It works better than the aftermarket one I had on my 1500. No more goofy tow mirror like the ones I'd slip over the stock 1500 ones. The rear doesn't sway or bounce anywhere near as much as the 1500 did.

My point is more that if he's towing heavy multiple times a month and stacking those trailers, he may just want to go for the 2500. If he gets the 1500, he spends money on the tow mirror, then he might want to upgrade the rear with air bags because the suspension might feel "squishy" with that weight, then he might want to go with shorter gears anyways to help the transmission hold gear better.

yillbs, your sig says you have 35s and a lift, so did I on my 1500. You said you towed just fine with it once...
I'm no expert at towing, I only had my 1500 for 2 years with a 4" lift & 34" tires and towed my travel trailer about 8-9 times in those 2 years (minus the day I picked it up and the days I took it back for a warranty repair). My 2500 has a 3" lift and taller tires than I had on my 1500. I've only towed the trailer twice with it, but I can tell you there is a big difference towing with that 1500 and the 2500.

The OP might be happy with the 1500. He'd be saving $$$$ daily in gas and that great deal he found. As a daily driver the 1500 wins hands down. I do miss that smooth, plush suspension for daily driving. I was just giving an opinion based on my towing experiences. It was an expensive lesson to learn getting the 1500 then going to a 2500 2 years later. And the OP will be towing a whole lot more than I ever did.

Again, just my $.02. The OP can take it for what it's worth. I'm glad your experience towing with your 1500 is different than mine was.
 
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norville

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My 1500 has the tow mirrors and they are great towing my 30 footer. I have the 5 speed with 3.92's , stock tires factory trailer brake and the 5.7 I always use a Weight Distribution Hitch and with this setup I would never consider going to a 2500 just no need for me. I never even considered towing my trailer without the WDH. It was $300 well spent. As a matter of note I had to keep reminding myself that I had a trailer back there running up the Poconos... I do have a superchips tuner and run the towing mode.

Although I'd love to have a 6.4....
 

Razorbackfan

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Judging from your sig it looks like you picked her up. That was a smoking good deal. I sold my '14 Outdoorsman 4x2 with 30k on her to a dealer for 25k. How has she been on the towing front?
 
OP
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TruckNoob

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Judging from your sig it looks like you picked her up. That was a smoking good deal. I sold my '14 Outdoorsman 4x2 with 30k on her to a dealer for 25k. How has she been on the towing front?

I just picked her up on the 24th. Thank you. I'll be towing a load of about 3k pounds tomorrow and will let you know. I won't be doing a bigger load until the middle or late part of January.
 

14RAM4X4

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I just picked her up on the 24th. Thank you. I'll be towing a load of about 3k pounds tomorrow and will let you know. I won't be doing a bigger load until the middle or late part of January.

I don't think you'll even notice 3K lbs behind you :favorites13:

That was a smoking hot deal on that truck.
 

mrsocks

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Enigmatic VIN results r/t rear end gear ratio

Looking up my VIN on a link obtained at "DodgeForum.com" as opposed to a Chrysler site (that seemed impressively official) gives me 3.21 on the former and a 3.92 on the latter. I can't seem to make any links from this forum work and was wondering if there are any visible differences between the two. I am towing a tandem axle trailer, electric brakes, and a weight around 5500-6000lbs wet n loaded.
The higher ratio will have me right at limits while the lower ratio gives (a little) margin.
Thanks all!
Socks
 

Ed loves guns

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Looking up my VIN on a link obtained at "DodgeForum.com" as opposed to a Chrysler site (that seemed impressively official) gives me 3.21 on the former and a 3.92 on the latter. I can't seem to make any links from this forum work and was wondering if there are any visible differences between the two. I am towing a tandem axle trailer, electric brakes, and a weight around 5500-6000lbs wet n loaded.
The higher ratio will have me right at limits while the lower ratio gives (a little) margin.
Thanks all!
Socks

This is the site I used. Not sure if its official or not. FCA US LLC Launch Page

Also keeping in mind that im a noob here asking for opinions in another section....
 

crash68

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Looking up my VIN on a link obtained at "DodgeForum.com" as opposed to a Chrysler site (that seemed impressively official) gives me 3.21 on the former and a 3.92 on the latter. I can't seem to make any links from this forum work and was wondering if there are any visible differences between the two.

Is the tag on the axle gone?
You can look up what your truck was built with here: http://www.ramtrucks.com/webselfservice/ram/Recall.html
Click on: Equipment Listing
 

Wings

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Here is my window sticker. What am I missing? I don't see anywhere where it tells me my gear ratio.....
 

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lukedukem

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The true answer to what the difference is between 3.21 and 3.92 is obviously 0.71. See how easy that was, No need for 3 pages and back and forth.

No need to thank me, it was all in a days work. :naughty:

:roflsquared:. but its not over yet, we are at 4 pages and counting.

Luke
 
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