An Engineer's Ultimate Guide To 3.21 VS 3.92 Axle Ratio

[Wild Bill]

Pictures describe it easily.

3.92 gear truck:

View attachment 162375

3.21 gear truck:

View attachment 162376

My 3.92...

 

[ferraiolo1]

He looks like he is compensating for something


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[theblet]

My 3.92... View attachment 164375

What is this a trans man on hormone therapy?

 

[HSKR R/T]

He looks like he is compensating for something


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He skipped leg day, which is why it's just his upper body in pic.

 

[Mountain Whiskey]

He looks like he is compensating for something


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Just being a man...

I suffer a similar fate.

 

[Fbird]

I was talking to this guy a few minutes ago. He's taking his dryer in for repairs. He could have used his 2020 Ram 1500 with 3.21 gears, but didn't want to risk smoking his transmission, so he loaded it up on this tandem trailer and hauled it in with his bike.

Smart man.

View attachment 164232

LOOK AT THE FORD HE'S RACING!!!

 

[Fbird]

Short story... my anemic (02 f150) 5.4 260 HP with 4.56's and 35" rollers and a TUNE...


up hill . or down hill....8500 lb trailer....moot....8.5 mpg

 

[spyder]

I'm no engineer, but I just sold my Rebel and bought a new Bighorn with 3.21s and empty truck seat of the pants feel is no different while fuel economy is much better. I'm happy with it.

Now, my Challenger has horrifically un-fun 2.76 gears. A winter project, budget dependent, is to go 3.73 or so in it, which should be a helluva lot more fun...although it sure runs nice with the 440 loafing along at 80mph down the freeway right now. I'll probably keep the third member on a shelf in the garage for quick swaps when I'm going to do a long road trip.

 

[Scram1500]

I'm no engineer, but I just sold my Rebel and bought a new Bighorn with 3.21s and empty truck seat of the pants feel is no different while fuel economy is much better. I'm happy with it.

The Rebel weighs more and also has 33 inch offroad tires, it makes sense that a much lighter Bighorn quad cab with 3.21 gears and 32 inch street tires would feel the same

 

[HSKR R/T]

I'm no engineer, but I just sold my Rebel and bought a new Bighorn with 3.21s and empty truck seat of the pants feel is no different while fuel economy is much better. I'm happy with it.

Now, my Challenger has horrifically un-fun 2.76 gears. A winter project, budget dependent, is to go 3.73 or so in it, which should be a helluva lot more fun...although it sure runs nice with the 440 loafing along at 80mph down the freeway right now. I'll probably keep the third member on a shelf in the garage for quick swaps when I'm going to do a long road trip.

Well, a Rebel with 3.92 will probably feel about the same as a Bighorn with 3.21 due to weight and tire size differences.

 

[HSKR R/T]

The Rebel weighs more and also has 33 inch offroad tires, it makes sense that a much lighter Bighorn quad cab with 3.21 gears and 32 inch street tires would feel the same

Beat me to it

 

[spyder]

Yep. I was concerned I'd lose some of the fun, but on the test drive it felt pretty much the same. I don't haul nearly often enough to worry about it, as long as it's still fun to drive while being much more useful of a truck.

 

[Idahoktm]

Yep. I was concerned I'd lose some of the fun, but on the test drive it felt pretty much the same. I don't haul nearly often enough to worry about it, as long as it's still fun to drive while being much more useful of a truck.

How is a Big Horn much more useful than a Rebel?

 

[Wirerat]

How is a Big Horn much more useful than a Rebel?

probably had cc rebel with smaller bed than qc bighorn.

 

[Idahoktm]

probably had cc rebel with smaller bed than qc bighorn.

Oh yeah, I see it in his signature. 9" more bed length has made the truck much more useful. As long as he thinks so, that's all that matters.

 

[spyder]

If you don't see how a longer bed, better fuel mileage, and a bigger fuel tank giving an extra hundred miles of range without refueling are more useful then you don't use a truck like a truck. Your TRX is badass and I'd love to have one to use as a toy, but it isn't capable of doing what I need a truck for so I didn't buy one. Doesn't bother me when folks have different needs.

 

[Idahoktm]

If you don't see how a longer bed, better fuel mileage, and a bigger fuel tank giving an extra hundred miles of range without refueling are more useful then you don't use a truck like a truck. Your TRX is badass and I'd love to have one to use as a toy, but it isn't capable of doing what I need a truck for so I didn't buy one. Doesn't bother me when folks have different needs.

Well crap. I didn't know better gas mileage and less trips to the gas station would make my truck more of a truck. I stand corrected.

I was giving you crap because you exaggerated. Lighten up Francis.

 

[Fbird]

1 really big consideration with gearing is...final gear ratio! I hunted for the 3.92 gear set as I already KNEW i was putting 35" tires on it. Up from say 32's..= almost 10% change in gearing so taking a 3.92 gear DOWN to 3.56 (or with 37's down to 3.29 ) it would be a bit difficult to go DOWN when starting with 3.21 as we all know the front diff sux. Regearing is a bit expensive ...and PITA so 3.21--> down to 2.69 @37"s....ughh

 

[CalvinC]

1 really big consideration with gearing is...final gear ratio! I hunted for the 3.92 gear set as I already KNEW i was putting 35" tires on it. Up from say 32's..= almost 10% change in gearing so taking a 3.92 gear DOWN to 3.56 (or with 37's down to 3.29 ) it would be a bit difficult to go DOWN when starting with 3.21 as we all know the front diff sux. Regearing is a bit expensive ...and PITA so 3.21--> down to 2.69 @37"s....ughh

This. All my trucks run 34 or 35" tires. If I planned to run OEM size tires forever, I'd honestly have no problem with the 3.21 idea.

 

[Mountain Whiskey]

Pull those Prius tires off that Bighorn and put some truck tires on it, the anemic 3.21s may well go down in milage (since that is what some buy a truck for, snicker...) trying to spin them. Especially if going at highway speeds.

I mean, since you pretend to have a truck, why not just go all the way and get the 6 banger and put an ebay 5.7 emblem on it to pretend there's a hemi under the hood too?