Lower gear ratio after lift and wheels tires

[Fordconvert]

Anyone drop to lower gears after lifting and adding wheels and tires. If so what difference did it make for you. I have been considering going to 3.73 in my 2300 AT4

 

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[gresham4wheeldrive]

When you lift your vehicle and add larger tires, the effective gearing changes. Bigger tires increase the rolling circumference, making the engine work harder to turn the wheels. This leads to slower acceleration, reduced throttle response, and more strain on the drivetrain.


To fix this, many install lower (numerically higher) gear ratios in the differentials. Lower gears help the engine turn bigger tires more efficiently, restoring acceleration, power, and drivability. For example, upgrading to 35-inch tires often works well with a 4.56 gear if the stock was 3.73. This also keeps the speedometer accurate and reduces stress on components.


Lower gears improve off-road performance and towing, but slightly increase engine RPM at highway speeds, reducing fuel efficiency. Choosing the right ratio depends on tire size, engine, and vehicle use to balance performance and efficiency.

 

[john151ama]

WHAT?! upgrading to 35” tires on 2020+ 2500/3500 and your recommending a gear change, LMAO. Going from a stock 34.1 inch tire to a 35 inch tire the dash would read 100mph and the truck would be going 102.6 mph.

Unless the truck is being lifted to fit 40”+ tires and solid steel wheels, there little need for gears. The hd truck is capable of towing 26k lbs+ any day, that’s 70x the load on the drivetrain than wheels and tires.

Greaham4wheeldrive must have been looking for views. I assume they are from my state of Oregon unfortunately. What a crap caned google response (to a post from 2023) that had no actual help to the long dated question..

With the gasser AT4X I have 3.73 and went from the stock 35” to 37” recently. Drives great especially with the 10 speed. Minimal difference in tires, absolutely no reason for gear change.

 

[kylant]

Greaham4wheeldrive must have been looking for views. I assume they are from my state of Oregon unfortunately. What a crap caned google response (to a post from 2023) that had no actual help to the long dated question..

With the gasser AT4X I have 3.73 and went from the stock 35” to 37” recently. Drives great especially with the 10 speed. Minimal difference in tires, absolutely no reason for gear change.

i am on the fence, mainly because i live in the mountains and drive the passes all the time.

 

[phobby]

Greaham4wheeldrive must have been looking for views. I assume they are from my state of Oregon unfortunately. What a crap caned google response (to a post from 2023) that had no actual help to the long dated question..

With the gasser AT4X I have 3.73 and went from the stock 35” to 37” recently. Drives great especially with the 10 speed. Minimal difference in tires, absolutely no reason for gear change.

A perspective of mine on your situation. The HD is geared for peak torque rpm to cruise 60-70mph(most common Hwy speed limits) . Going from 35” to 37” the speedometer would be 4ish mph slow. Relatively this offset would be appealing to me bc it moves peak tq and mpg rpm to the 64-74mph range. Since 65 and 70mph speed limit is a lot more common around here, the truck would likely get better mpg overall.

 

[R467X]

I am of the opinion that calibrating your speedometer over dealing with gear change/rear end is the way to go. Exception being if you tow close to max capacity. These trucks will handle a 35 and even a 37 without much stress as long as your speedometer is properly calibrated. You'll know when it's way off when it feels like there's something wrong with your truck when accelerating, decelerating and trying to maintain speed.