Changing 3:21 to 3:92

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Wayne E

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Is it a big job to change my 2018 Express 3:21 to 3:92's? I'm guessing it's not just pulling out and swapping the gears and axles? And yes I did a search and couldn't come up with anything.
 

Ohio5pt7

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2 or 4wd? If 2wd simple as swapping your rear gear. 4wd you need a new front diff and swap rear. I've seen upwards of 4k to swap a 4wd.

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tron67j

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If your looking to tow a heavier travel trailer you might not achieve your goal, the weights across the board do not change, the only increase is 2k lbs increase in towing capacity while keeping tongue weight the same. Only way to achieve that is more weight behind the trailer axle which can increase sway that might not be all mitigated with sway bar. For what it would cost and minimal benefit, have you considered the trade up to a 2500? Your value plus up to $4k upgrade is maybe new truck territory. Good luck.
 

NJMOPAR

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I estimated upwards of $1700 just to change my 3:55 std. rear to a limited slip.
No ratio change so nothing to change up front, just swapping the rear chunk for a posi and the labor.
Just to have two stripes on burnouts? Not worth it.

Food for thought...
 
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Wayne E

Wayne E

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2 or 4wd? If 2wd simple as swapping your rear gear. 4wd you need a new front diff and swap rear. I've seen upwards of 4k to swap a 4wd.

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4WD. Just looking for a little more get up and go! Pulled two quads on an aluminum trailer this past weekend and would just like some better gearing. Curious is all
 

Ohio5pt7

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4WD. Just looking for a little more get up and go! Pulled two quads on an aluminum trailer this past weekend and would just like some better gearing. Curious is all
Honestly kinda surprised by that I tow a 7500lb tt and can pass at will including thru mountains. It doesnt notice the trailer and rzr.

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Wayne E

Wayne E

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Honestly kinda surprised by that I tow a 7500lb tt and can pass at will including thru mountains. It doesnt notice the trailer and rzr.

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Oh the truck had no problem at all. Was passing doing 110 km/h easily, was just wanting, not needing better gearing
 

tap4154

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Oh the truck had no problem at all. Was passing doing 110 km/h easily, was just wanting, not needing better gearing

Sounds like your gearing is fine, you're just suffering "The Grass is Always Greener" syndrome. Do you really want to pay more for the reduced gas mileage?
 
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If you don't have larger than 35" tires I wouldn't waste my money on a gear swap, especially if you are just going to go to 3.92s from 3.21s, you should at least gear up to 4.56s and that would allow you to run up to a 37" tire set up and easily move 35" tires ... I geared to 4.88s only because I have 37s on my truck ... save your money and use it towards something else
 
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Wayne E

Wayne E

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Sounds like your gearing is fine, you're just suffering "The Grass is Always Greener" syndrome. Do you really want to pay more for the reduced gas mileage?
More curiousity is all. Wanting to know if it was easy or more trouble than anything. Sounds like more trouble than anything.
 

crash68

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More curiousity is all. Wanting to know if it was easy or more trouble than anything. Sounds like more trouble than anything.
The rear axle ratio change is best left to the professionals unless your going to swap the whole axle. The front you probably can find a low mileage one in a local salvage yard, there is no swapping the front gear like the rear. The front is a little more work to swap but is something that can be tackled by a lot home mechanics.
 

phantomfixer

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The world has gone crazy, times are tough...keep what you have and save your money.Your truck will do just fine with what you have
 

Ludville1

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I estimated upwards of $1700 just to change my 3:55 std. rear to a limited slip.
No ratio change so nothing to change up front, just swapping the rear chunk for a posi and the labor.
Just to have two stripes on burnouts? Not worth it.

Food for thought...

^^^This! Was wanting to go to 4.56 front and rear (currently has 3.55's) along with a LSD for my truck. Parts and labor would probably cost upwards of $3K to accomplish this. Took the fun right out of this idea! Emailed 3 different shops for a quote, no one even responded. If I felt comfortable doing the work myself, I would do it in a heartbeat! I'm sure that the truck would be a blast to drive, as it is already a beast.
 

Wild one

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More curiousity is all. Wanting to know if it was easy or more trouble than anything. Sounds like more trouble than anything.

Put a set of long tube headers on it and buy an unlocked pcm then get it tuned,it'll cost you about the same as regearing it in Canada,and will add more fun to the drive,lol
 

farout75

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My 14 RAM 1500 window sticker sai it had 355 gear ratio. But in truth it turned out it had 321. FCA had a good number of these happen. A class action was started by a Attorney and most went with him. Instead I dealt with FCA myself. The cost to change the gears was more than $2,500. FCA asked me what would it take to make me live with the truck? I asked FCA to change the gears as the window sticked stated. FCA offered to buy back the truck and me to pay 35 cents per mile for use. That was unacceptable for me. We came up with FCA putting on remote start and a folding truck bed cover. Retail sales for these items came to about $1,700. This was the best compromise that we settled on. Those who went with the attorney as I understand it got much less.

Changing gears is a huge task, and you might be better trading it in for what you really want.
 

Narg

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add a Pedal Commander, may not help gearing but will feel better! :)

I had one of those once. It was great until it locked up the system in the truck making it not work right. I've also read about these causing failures on the highway. Not good. And, never again. But it did seem nice to have more response from the pedal, as simple of a change as it is.
 

bchap05

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I had one of those once. It was great until it locked up the system in the truck making it not work right. I've also read about these causing failures on the highway. Not good. And, never again. But it did seem nice to have more response from the pedal, as simple of a change as it is.


Never heard this. Had mine on for 3 years worked great, I only took it off because I bought a Pulsar which gave me the same throttle response but with actual power addition.
 

Ohio5pt7

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I use both the pulsar and pc no issue so far

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