3.21 gear good and bad

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Bigfoots03hd

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I’ve been looking at new Ram trucks and I see a lot of them have the 3.21 gear in them. I currently have a 2016 Ram 1500 R/T with 3.92 gear. Looking for thoughts and opinions on 3.21 gear Thanks
 

NorthStar1

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First, I tow so my conventional way of thinking is go 3.92.

Added to this, I always test drive both ratios when looking at a new truck and let the seat of my pants help make the purchase. I’ve done this every time I’ve purchased a new Ram - that’s why I’ve always purchased and currently own a Ram with 3.92s (unless it was a Ram 2500 and then I purchased the 4.10 axle all three times).
 

Hasek

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I’ve been looking at new Ram trucks and I see a lot of them have the 3.21 gear in them. I currently have a 2016 Ram 1500 R/T with 3.92 gear. Looking for thoughts and opinions on 3.21 gear Thanks

anything specific?
 

Neil E

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I would not downgrade for any reason , the gas mileage difference is not worth it. If you want to get 2 mpg better, just drive slower and frugal. It would take a long time to make up the cost to downgrade.
 

pacofortacos

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3.21 gets significantly better mpg over 70 mph.

Tooling around in the country side under 50 mph, give me the 3.92's all day long - absolutely perfect combo with the 8 speed.

Towing most sane loads with a 1500 - not a big difference due to the 8 speed.
 

Firebird

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Just my personal opinion, but 3.92 gears were mandatory for me. I really didn’t like the 3.21’s at all
 
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I had 3.21s and while my truck was stock it was just fine ... as soon as I lifted the truck and threw the 37s on I knew eventually I would have to regear ..... if you are just planning to have a truck without towing and adding bigger than 35" tires then you definitely want to stay away from the 3.21s ...
 

yakalong

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3.21 are fine for most. It will pull a bass boat or similar just fine. However if you are already worried that 3.21 will not be sufficient then I’d go with 3.92.
 

MoPowered

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Boy oh Boy, I hesitate pulling the trigger on a newer Power Wagon because they only come with the 4:10’s. I’ll keep my 12 with the 4:56’s and 37’s. When we threw 37’s on my Brother’s 17’ 2500 he went and bought a programmer he was so displeased by the drop in response. I didn’t think it was too bad, I wouldn’t have been happy either but I din’t tell him that.
 
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Boy oh Boy, I hesitate pulling the trigger on a newer Power Wagon because they only come with the 4:10’s. I’ll keep my 12 with the 4:56’s and 37’s. When we threw 37’s on my Brother’s 17’ 2500 he went and bought a programmer he was so displeased by the drop in response. I didn’t think it was too bad, I wouldn’t have been happy either but I din’t tell him that.

I was going to go with the 4.56s but everyone said to go with the 4.88s since I had the 37s... I love the truck ... would you go with 4.88s on the 37s now that you have been driving it for so long ?
 

pacofortacos

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Boy oh Boy, I hesitate pulling the trigger on a newer Power Wagon because they only come with the 4:10’s. I’ll keep my 12 with the 4:56’s and 37’s. When we threw 37’s on my Brother’s 17’ 2500 he went and bought a programmer he was so displeased by the drop in response. I didn’t think it was too bad, I wouldn’t have been happy either but I din’t tell him that.

If the new PW comes with the 8 speed trans, I don't think you would be too disappointed in the 4.10's.
You would notice a bit of a drop in the 8th gear vs. 6th with the 4.56's, but on the bottom end the 4.10's with the 8 speed trans will be far superior to your current 6 speed with 4.56 gears.
 

Fatbob Frank

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Good choice.
I have 3:21s and 90% of the time I'm empty and alone so it's fine.
But those other 10% really make me miss lower gears...
 

dwade

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Bump.

I've got a 2015 Tradesmen 1500 4x4 with 3.21 gears and the 6 speed transmission and pull a travel trailer that weighs 7k lbs. I've thought about swapping out gears and have been searching the threads about it looking for information. I plan on leaving stock tires on it. While most of our camping has been fairly close to home I'd like to head south to the Carolina's and will be going through the mountains and fear the gears are going to hinder me greatly. I'm reading 3.55 and 3.92 gears. I know that I will miss the good gas mileage (20-22mpg) but know I need higher gears for power.
 

10mmGlock

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The 3.92's I had in my 2018 make me really miss the truck, my 2020 has 3.21's and it definitely feels a lot more sluggish.
 

Redfour5

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3.21 gets significantly better mpg over 70 mph.

Tooling around in the country side under 50 mph, give me the 3.92's all day long - absolutely perfect combo with the 8 speed.

Towing most sane loads with a 1500 - not a big difference due to the 8 speed.
I had a 3.92 and it was great with my 6500 lb travel trailer loaded. I had the big gas tank also. So, my old one gave out and they still offered me 21K after 75K miles when they only offered me 15K about 15 or so months ago.

A built to serve was on the lot being looked at by more than one person while I was there still waiting on the verdict for my 2015 Outdoorsman. It checked every box except it had the 3.21 gears including the tow package, off road package and it is essentially blacked out and had more than what I was looking at 15 or so months ago. My goal then was to get one for about 35K. So, I dithered and that evening saw this video by TFL with a FULLY loaded 3.21 5.7 and said, OK... https://www.youtube.com/watch?v=yWf8L2g9Z4I

I do about a 500/600 Hundred mile first tow this weekend, 100+ degrees at the destination and 250+ miles each way one pass and then down into spokane WA. So, here we go... Oh, in the video, the RAM beat the latest greatest Ford F150 too.
 

Gero

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I tow a 6000 TT with a 3.21 and its been fine. Never felt like I needed more power. The truck is 100% stock with the stock 20s. No plans to run 35 or 37a and definitely no plans to lift it. I enjoy the super low rpm when cruising on the highway. I easily get 21mpg empty and even higher depending on wind.

The 8spd makes up q big difference.
 

Redfour5

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I had a 3.92 and it was great with my 6500 lb travel trailer loaded. I had the big gas tank also. So, my old one gave out and they still offered me 21K after 75K miles when they only offered me 15K about 15 or so months ago.

A built to serve was on the lot being looked at by more than one person while I was there still waiting on the verdict for my 2015 Outdoorsman. It checked every box except it had the 3.21 gears including the tow package, off road package and it is essentially blacked out and had more than what I was looking at 15 or so months ago. My goal then was to get one for about 35K. So, I dithered and that evening saw this video by TFL with a FULLY loaded 3.21 5.7 and said, OK... https://www.youtube.com/watch?v=yWf8L2g9Z4I

I do about a 500/600 Hundred mile first tow this weekend, 100+ degrees at the destination and 250+ miles each way one pass and then down into spokane WA. So, here we go... Oh, in the video, the RAM beat the latest greatest Ford F150 too.
Well, did the trip and...was pleasantly surprised. The trip was from Helena Montana to Spokane WA about 300 miles. I averaged 8 mpg with the 3.21 gears. The lyometer said 8.6 mpg. I started with 1300 miles and for that first 1300 miles I've averaged in the close to 13 mpg during break in. Since I got back, I'm over 15 mpg mixed driving without the trailer first hundred miles. I'm thinking I'll probably do better once I've got a few thousand miles on it.

Anyway towing, there was plenty of power but it is delivered a bit differently than 3.92 gearing and you can tell that the transmission is doing more work than with a 3.92. I was honestly contemplating a 2500 but couldn't get a decent trade on the new 1500 and now I'm fine with that. The trip had two passes and the truck was just fine. The only thing I missed was my KO2's on the 2015. The Falken OWL's on 20 inch wheels at 40 psi kind of "wallow" a bit while KO2's at 50 psi are stiff and give a better road feel while towing. The OWL's are wonderful when not towing and just OK for towing. I prefer the harder ride but they are acceptable especially since i'm not going to spend 1K for new tires right now. I will actually put the Falkens at 45 for the next trip.

So, IF you have a trailer in the weight range of mine (6500ish) and are within your payload including tongue weight, I would not let the 3.21 gears get in the way of your decision. IF you can order 3.92's and don't mind the hit on mileage overall, do it, but the 3.21 gears WITH the 8 speed transmission does a very good job and the qualitative improvements in ride since my 2015 are very noticable. One of my concerns was the fact that I have the Bighorn level 1 and I was worried about the amount of information the instrument cluster (3.5 TFT) would provide vs the level 2, 7 inch TFT (instrument cluster). It provides everything you need including trailer related info. I have the tow package. You do have to drill down into the info a bit more than the 7 inch TFT, but it's there and just a matter of getting used to it.

So, I'm content and looking forward to a 100K miles in it. Now if it just doesn't develop a hemi tick...
 

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