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3:21 vs 3:92 Gears

Scap

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I must have messed up the math. I converted the 65mm sidewalls of the stock tires then x2 for top and bottom and added it to the 18” rims which equals 23.118”. I did the same with the 55mm sidewalls of the new tires and added it to the new 20” rim and got 24.33. Resulting in the new height being 1.212” taller. Is this not correct? I’m awful at math so feel feee to correct me.

The 55 and 65 are aspect ratio.
Width versus sidewall height.
Take your width multiply by the aspect ratio to get a sidewall dimension.
Convert to inches.
Rim diameter plus sidewall plus sidewall = tire diameter.
275/65/18
285*0.65= 178.75mm = 7.03"
18+7.03+7.03= 32.06"

275/55/20
275*0.55= 151.25mm = 5.95"
20+5.95+5.95= 31.9"
 

c3k

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The 55 and 65 are aspect ratio.
Width versus sidewall height.
Take your width multiply by the aspect ratio to get a sidewall dimension.
Convert to inches.
Rim diameter plus sidewall plus sidewall = tire diameter.
275/65/18
285*0.65= 178.75mm = 7.03"
18+7.03+7.03= 32.06"

275/55/20
275*0.55= 151.25mm = 5.95"
20+5.95+5.95= 31.9"

What he said.

By aspect ratio, he means it's a percentage of the tread width. Since most tires are giving tread widths in mm, the aspect ratio is multiplied by that treadwidth and that gives you ONE sidewall height...in millimeters. Convert it to inches and multiply by two. That's how much rubber you've got, top and bottom. Add the wheel diameter and that gives you the total diameter.
 

Willwork4truck

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Is it safe to assume that the Limiteds that come with 22 inch rims have 3.92’s?
No, mine is 3.21. Another gripe, they needed to have kept the 3.55’s IMHO.
 
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Dewey

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No, mine is 3.21. Another gripe, they needed to have kept the 3.55’s IMHO.
Yup. They tease us with the 3.55’s listed on the Build & Price but then tell you it’s only for the V6 only it appears. I think they would be a nice happy medium for those on the fence between 3.21 and 3.92.
 
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killerformula

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I got the 3.92 in the 2022 Laramie I ordered for a couple reasons. The biggest one was that this truck isn’t my only car and I bought it in the first place because I really needed a truck available to me for my projects etc. because of that I tried I spec everything on the truck to maximize its capabilities. I got the largest fuel tank, the longest bed I could, the v8 engine and the bed utility group, 4 wheel drive and the ORG. If I was going to bother buying a ram I wanted to have it be able to do the most a 1500 could.

I was never worried about the gas mileage, figured it was the wrong vehicle to buy and worried about that. The 3.92 will help me pull a boat out of the water a little easier, tow the occasional trailer with a bit less fuss and help me enjoy the occasional off roading I like to do because my throttle response will be just a little better.
 

Mountain Whiskey

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How does this thread exist when all the facts are laid out in the thread that is a sticky?

The facts of over 2000 posts there boil down to this:

3:21 gears = Girly Gears. These are used on grocery getters that typically run Prius tires. These can be viewed in parking lots of grocery stores (typically a Trader Joes or local organic food store), Ulta stores and nail salons waiting to pick up wives and receive reward of borrowing balls for the ride home.

3.92 gears = Truck gears. These are used on trucks that haul, tow, off road and generally have fun. These maintain your Hemi power as you increase tire size and weight. They can be viewed at the local Home Depot (contractor side), liquor store, off road trails, hunting camps and strip clubs (Please when viewed parked on the side of the building and rocking a bit, do not disturb).

All these fun facts and more are laid out in the other thread:

 

djevox

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How does this thread exist when all the facts are laid out in the thread that is a sticky?

The facts of over 2000 posts there boil down to this:

3:21 gears = Girly Gears. These are used on grocery getters that typically run Prius tires. These can be viewed in parking lots of grocery stores (typically a Trader Joes or local organic food store), Ulta stores and nail salons waiting to pick up wives and receive reward of borrowing balls for the ride home.

3.92 gears = Truck gears. These are used on trucks that haul, tow, off road and generally have fun. These maintain your Hemi power as you increase tire size and weight. They can be viewed at the local Home Depot (contractor side), liquor store, off road trails, hunting camps and strip clubs (Please when viewed parked on the side of the building and rocking a bit, do not disturb).

All these fun facts and more are laid out in the other thread:

6F5D1B5D-6720-4C33-84CF-DEE9A6B60471.jpeg
 

bigdodge

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How does this thread exist when all the facts are laid out in the thread that is a sticky?

The facts of over 2000 posts there boil down to this:

3:21 gears = Girly Gears. These are used on grocery getters that typically run Prius tires. These can be viewed in parking lots of grocery stores (typically a Trader Joes or local organic food store), Ulta stores and nail salons waiting to pick up wives and receive reward of borrowing balls for the ride home.

3.92 gears = Truck gears. These are used on trucks that haul, tow, off road and generally have fun. These maintain your Hemi power as you increase tire size and weight. They can be viewed at the local Home Depot (contractor side), liquor store, off road trails, hunting camps and strip clubs (Please when viewed parked on the side of the building and rocking a bit, do not disturb).

All these fun facts and more are laid out in the other thread:

because mods have more to do than move threads around:)
 

SnowBlaZR2

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I got the largest fuel tank, the longest bed I could, the v8 engine and the bed utility group, 4 wheel drive and the ORG. If I was going to bother buying a ram I wanted to have it be able to do the most a 1500 could.
Well, everything except haul a decent load. :LOL:
 

SnowBlaZR2

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I can haul my Häagen-Dazs just fine
So can this:

be88f83157892a5ec84b34305deab86a.jpg
 

IvoryHemi

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How does this thread exist when all the facts are laid out in the thread that is a sticky?

The facts of over 2000 posts there boil down to this:

3:21 gears = Girly Gears. These are used on grocery getters that typically run Prius tires. These can be viewed in parking lots of grocery stores (typically a Trader Joes or local organic food store), Ulta stores and nail salons waiting to pick up wives and receive reward of borrowing balls for the ride home.

3.92 gears = Truck gears. These are used on trucks that haul, tow, off road and generally have fun. These maintain your Hemi power as you increase tire size and weight. They can be viewed at the local Home Depot (contractor side), liquor store, off road trails, hunting camps and strip clubs (Please when viewed parked on the side of the building and rocking a bit, do not disturb).

All these fun facts and more are laid out in the other thread:

3.92 vs 3.21 side-by-side

BE1ABB27-97E3-4E29-9927-2D746E3CA468.png
 

killerformula

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Well, everything except haul a decent load. :LOL:
Absolutely! If I was worried about payload I would have ordered a Ford maverick!!

 

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