Find Your Effective Gear Ratio With This Equation

Ian shows you how to find the effective gear ratio on your vehicle when you upgrade to bigger tires with this equation on a PowerNation Extra tech tip. It can affect things like shift points in the transmission, engine RPM, and even acceleration from a dead stop since the tire now rotates a different number of times than a stock one. Stay tuned for more tech from PowerNation Extra.

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[critflame]

Brilliant and simple, , , just what I was looking for

[Boogaloo_Baloo]

Simple and straight to the point. I love it.

[MMALLDAY]

Back when PowerNation was still cool 😢

[romelrodriguez]

I remember this guy on his show on Spike TV.

[brylyn]

Jesus does he drive his car with his head out the window

[halfbakedcontrarian]

This is a great video. Really helpful for a knucklehead like myself.

[MauGT]

Really good video sir. I have one question please, I'm changing the tires in my car, I had 265 wide and now it is 325 wide, the tall is about the same in both cases, my question is if this calculation is also useful considering the tire width instead of the height, thank you very much!

[harrisondanner]

My current set up is 3.50’s in my Dana 44 and my Chrysler 9.25 rear axles and I have 33’s right now and my truck is extremely slow. Especially accelerating. I think the first thing I will do is get the gears swapped to bigger than I should and go to 4.10’s.

[gunsandhorsepower]

What gear radio would be good for the mud got about 500hp with 37 boggers

[latortugaoffroad]

Hi Good information thank you for I wonder if you could help me with something I have tires 27 I increase to 31 My ratio is 5.12 It's a Geo tracker 1996 I use your calculation and it gives me 5.88 When I try to buy one nobody seemed to know what I'm talking about Do I mind doing something wrong can you help Me find the right ratio?

[tedwilson]

.12 x the tire diameter will give you the ratio you need, choose the closest ratio from factory

[Raptor-]

Is 325lb ft torque good for larger tires?

[irplesm]

going from 18" to 20" with 3.15 gears would require an update rear gear to 3.5. my question is, do i need to calibrate the speedo or will it be reading it correctly w mph and distance travelled.

[AnubisReviews]

Went through a dozen videos to figure this out. My Bronco II has 26.5 inch stock tires and 3 stock final drives. Now it has a set of 29s and I have been having issues with shifting. Been looking to change the final drive but couldn't find ANYTHING on the math. This guy has it broke down to where even a dummy like me can figure it out.

[terranhightower]

When I did my lift and tires 14 years ago, I went from 28 inch tires to 31 and had a gear ratio of 3.27 in the rear. Per this math I should get 3.62 new gear ratio (closest would be 3.72). I made a guess at the gears I should put in and chose 4.11 gears on a 5 speed manual tranny. I have issues with keeping up with traffic from a dead stop, keeping up to speed on hills and CANNOT tow worth a damn with this gearing choice. I have to press the pedal 3/4 to Wide Open Throttle while towing and this was with a 5x10 trailer with minimum items on it. I would have been better suited at 4.56 for gear choices according to the tables that are out there. If I followed this math, I'd be in a worse position than I already am.

[Ahd]

Does it affect by the transmission ratio? I mean 1st 2nd ratios?

[linthicum]

So if my Jeep has 31 tires and I put 33 on and my gear ratio is 3.43 it only goes to 3.65 hears doesn’t sound rite

[Stop_the_cap]

Wat gear ratio should o be running on 33.5?

[Commandos]

My vehicle
2008 nissan navara d40
33 12.50 15 inch tire

Ring & pinion Which fits ???

Can you link ?



I'm from Turkey Istanbul

[ar]

HOW ... do I figure axle ratio using bigger tires on back, smaller on front with 4x4 drive? my question applies to an ATV