What Are Gears in a Car? Gear Ratios and What 1st-6th Do
Gears are sets of toothed wheels in a transmission that change how many times the engine turns for each turn of the wheels. A low gear such as 1st multiplies engine torque to get a stopped car moving, while a high gear such as 6th lets the wheels spin faster with the engine turning slower. This guide uses published ratios from a 6-speed Toyota GR Corolla and an 8-speed ZF automatic, plus owner’s manual wording from Honda, to show what each gear does and how manual, automatic, CVT and dual-clutch transmissions differ.
Basics Of Car Gears
Best Transmission Basics Read
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How a Transmission Works for Beginners: Manual, Automatic, CVT and Drivetrain Systems Explained
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A car needs gears because an engine only works well over a limited speed range, while the wheels have to turn from a crawl to highway speed. Per fueleconomy.gov, most conventional transmissions use a fixed number of metal gears to control the ratio between engine speed and wheel speed. Change the gear and you change that ratio.
A ratio of 3.538 to 1 means the engine turns 3.538 times for each turn of the transmission’s output shaft. A second ratio in the final drive, called the differential ratio by Toyota, multiplies it again. The lower the gear number, the bigger the ratio: more multiplication of torque, and a slower road speed for the same engine rpm. Toyota describes 1st gear as the one for moving from a full stop, with 2nd gear and higher for faster speeds.
The table below uses the numbers Toyota publishes for the 6-speed intelligent Manual Transmission in the GR Corolla, a 1.6-liter turbo three-cylinder rated at 273 lb-ft of torque and a 7,200 rpm redline. The last three columns are calculated from those published ratios and the 235/40R18 tire size Toyota lists, ignoring tire slip and driveline losses.
| Gear | Gear ratio | Final drive | Overall ratio | Road speed per 1,000 rpm | 273 lb-ft multiplied by overall ratio |
|---|---|---|---|---|---|
| 1st | 3.538 | 4.058 | 14.36 | about 5 mph | about 3,920 lb-ft |
| 2nd | 2.238 | 4.058 | 9.08 | about 8 mph | about 2,480 lb-ft |
| 3rd | 1.535 | 4.058 | 6.23 | about 12 mph | about 1,700 lb-ft |
| 4th | 1.162 | 4.058 | 4.72 | about 16 mph | about 1,290 lb-ft |
| 5th | 1.081 | 3.450 | 3.73 | about 20 mph | about 1,020 lb-ft |
| 6th | 0.902 | 3.450 | 3.11 | about 24 mph | about 850 lb-ft |
Two things stand out. First, the overall ratio falls from 14.36 in 1st to 3.11 in 6th, so the same engine torque is multiplied more than four times as much in 1st. That is why a car pulls away in 1st and why a low gear helps on a steep road. The torque figure is the engine’s peak multiplied through the gearbox and final drive; the real force at the tires is lower after losses, and this car’s all-wheel-drive system adds gearing that is not included.
Second, the gaps between gears shrink toward the top. Dividing one ratio by the next gives the step: 1.58 from 1st to 2nd, 1.46 from 2nd to 3rd, 1.32 from 3rd to 4th, 1.07 from 4th to 5th and 1.20 from 5th to 6th. A step of 1.58 means an upshift from 1st to 2nd drops engine speed to about 63 percent of what it was, while 5th to 6th drops it only to about 83 percent. Taken at the 7,200 rpm redline, the same arithmetic puts 1st gear near 38 mph and 2nd near 60 mph, which is why a low gear runs out of speed so quickly.
Want the mechanics behind this? How gears work in a car walks through how the meshing gears pass power from the engine to the wheels.
Manual Transmission
In a manual transmission the driver picks the gear. Toyota’s explanation is that the driver presses the clutch pedal to free the transmission from all gears, moves the gear stick to the needed gear, then releases the clutch pedal gradually to engage it. The numbers on the shift knob match the gears, and R stands for reverse. Our beginner guide to shifting a car covers the technique step by step, and manual vs automatic compares the two for buyers.
Honda’s owner’s manual for the 2025 Civic Hatchback adds practical rules for its manual transmission. It says to fully depress the clutch before moving the lever, to pause for a few seconds before shifting into R (or briefly select a forward gear) so the gears stop and do not grind, and not to rest your foot on the clutch pedal when you are not shifting, because that can wear the clutch out faster. It also says not to shift to R before the car has come to a complete stop, since that can damage the transmission. The full text is on Honda’s shifting page for manual models.
Some manuals can help with the engine speed matching. The Honda manual describes its rev match system as adjusting engine rpm to match the optimal speed of the gear about to be engaged, and says it can be turned off from the screen. Toyota lists rev-matching on the GR Corolla’s 6-speed manual too. The system is an aid, not a replacement for the clutch: Honda lists conditions where it will not activate, such as shifting into 1st gear from a higher gear.
Automatic Transmission
An automatic does the same job with a computer choosing the gear. Toyota notes that an automatic transmission still has gear sets and a clutch, but the selection of the gear and the release of the clutch are controlled by an on-board computer, which is why the shifter is simpler: P for park, R for reverse, N for neutral and D for drive. Some automatics also let you select the lowest gears, such as 1 or 2, to help with steep roads, and some offer a manual mode or plus and minus shifting. Toyota adds that most vehicles will not let you downshift into a very low gear at high speed, because that could damage the engine. If you are new to the lever, how to drive an automatic transmission car explains each position.
ZF publishes the ratios for its 8HP family. The data sheet for the 8HP90 version lists these standard ratios, with the step to the next gear calculated by dividing one ratio by the next:
| Gear | ZF 8HP90 ratio | Step to next gear |
|---|---|---|
| 1st | 4.714 | 1.50 |
| 2nd | 3.143 | 1.49 |
| 3rd | 2.106 | 1.26 |
| 4th | 1.667 | 1.30 |
| 5th | 1.285 | 1.28 |
| 6th | 1.000 | 1.19 |
| 7th | 0.839 | 1.26 |
| 8th | 0.667 | – |
The total spread, 1st divided by 8th, is 7.07, matching the 7.0 spread ZF quotes for the 8HP. Compared with the six-speed manual above, whose spread is 3.538 divided by 0.902, or about 3.9, the eight-speed covers a wider range in smaller steps. ZF also says the 8HP needs only 5 shift elements for 4 gear sets, with 3 multidisk clutches and 2 brakes, and that only two shift elements are open in any gear, which reduces drag losses. The 8HP90 sheet is a transmission data sheet, not a car, so the ratios you find in a specific model depend on the maker’s choices.
CVT and Dual-Clutch Systems
A continuously variable transmission, or CVT, has no fixed gears. Per fueleconomy.gov, it uses a pair of variable-diameter pulleys connected by a belt or chain that can produce an infinite number of engine-to-wheel speed ratios. Its listed advantages are seamless acceleration without the jerk of gear changes, no frequent downshifting or gear hunting on hills, and better fuel efficiency, mostly in stop-and-go driving rather than steady highway speed.
Toyota explains the same idea as pulley halves moving together or apart: with the driven pulley halves pressed together and the driver pulley halves apart, that is a low gear, and the reverse is a high gear. Toyota also says its Dynamic-Shift CVT has a real first gear, called a launch gear, for the early part of a drive that Toyota puts at 1 to 25 mph, before the pulleys take over.
Many CVTs still offer fixed steps for drivers who want them. The 2025 Honda Civic Hatchback has a 7-speed manual shift mode operated by paddle shifters, which Honda says is useful when engine braking is needed; in Sport mode you can only pull away in 1st speed. See Honda’s shifting page for CVT models for the full rules.
A dual-clutch transmission, or DCT, is closer to a manual. Per fueleconomy.gov, DCTs operate much like manual transmissions except that they use two clutches and automatic shifting, and they are generally not quite as smooth as regular automatics. Which models use one is covered in what cars have a dual-clutch transmission.
Factors Influencing Gear Choice
No maker publishes a single best rpm to shift at that fits every car, so the guidance that matters is the one in your own owner’s manual. The statements below come from the Honda and Toyota material quoted in this guide and show what the makers actually say about choosing a gear.
| Situation | What the maker says | Source |
|---|---|---|
| Going downhill in a manual | The shift-down indicator will not prompt a downshift for engine braking; it is up to the driver to downshift. Shift down at the appropriate vehicle speed. | Honda 2025 Civic Hatchback manual |
| Before any downshift | Make sure the engine will not go into the tachometer red zone, which can severely damage it. | Honda 2025 Civic Hatchback manual |
| Slowing for a turn in a CVT | The 7-speed manual shift mode is especially useful when reducing speed temporarily before making a turn. | Honda 2025 Civic Hatchback manual |
| Steep roads in an automatic | Some automatics allow selecting the lowest gears, such as 1 or 2, for ascending and descending steep roads. | Toyota, Types of Transmissions |
| Downshifting at high speed | Most vehicles will not allow a downshift into a very low gear at high speed, because it could damage the engine. | Toyota, Types of Transmissions |
| Slippery surface with paddles | Using the paddle shifters on slippery surfaces may lock the tires; the manual shift mode then cancels and returns to D. | Honda 2025 Civic Hatchback manual |
Honda also says that road and traffic conditions may require shifting at times other than those the indicators show, and that driving at engine speeds in or over the tachometer red zone can cut the fuel supply and cause a slight jolt. For more on picking the right gear on the road, see the different gears used for driving and when to use them.
Innovations In Gear Technology
More gears let the engine sit at an efficient speed more often. Fueleconomy.gov puts numbers on this, compared with a 4-speed automatic:
| Transmission | Potential efficiency improvement vs a 4-speed automatic | Source |
|---|---|---|
| 6 gears | 2% | fueleconomy.gov |
| 7 gears | 2% to 3% | fueleconomy.gov |
| 8 gears | 3% to 4% | fueleconomy.gov |
| CVT | 3% to 4% | fueleconomy.gov |
| Dual clutch | 3% to 4% | fueleconomy.gov |
These are potential gains from the National Academies data fueleconomy.gov cites, not a promise for any one car. ZF says its 8HP delivers about 3 percent lower average consumption and CO2 in upper and middle class vehicles, and that a mid-size 8HP70 weighs 87 kg with oil. Fueleconomy.gov also notes that automatic transmissions are less efficient than manuals because of parasitic losses.
Maintenance Tips For Car Gears
The gear parts themselves are sealed inside the case, so the owner’s habits and the maker’s schedule matter most. From the Honda manual: do not rest your foot on the clutch pedal in a manual, come to a complete stop before moving between D and R, and use the shift position indicator to confirm the lever position before pulling away. Honda also warns that a shift lever left in a hot parked car can be extremely hot to the touch.
- Transmission fluid type and change interval are set by the maker. Look them up in the owner’s manual or ask a dealer; do not guess a number.
- If the transmission system indicator blinks while driving, Honda says there is a problem with the transmission, to avoid sudden acceleration and to have it checked by a dealer as soon as possible.
- A car that will not change gears needs diagnosis, not a longer drive: see why a car may not be shifting gears and how to know if you need transmission fluid for first checks.
Frequently Asked Questions
What Does The Gear 1, 2, 3, 4, 5 Mean?
The numbers rank the gears from lowest to highest. Toyota describes 1st gear as the one for moving from a full stop and 2nd gear and higher as the ones for faster speeds. A higher number means a lower ratio, so the wheels turn faster for each engine revolution.
What Are Gears In A Car Used For?
Gears let the engine run at a useful speed while the wheels turn at very different speeds. Per fueleconomy.gov, a transmission controls the ratio between engine speed and wheel speed. Low gears multiply torque to pull away or climb, and high gears keep engine speed down at road speed.
What Does 1st, 2nd, And 3rd Gear Do?
In the 6-speed Toyota GR Corolla, 1st gear multiplies engine torque by about 14.4 through the transmission and final drive, 2nd by about 9.1 and 3rd by about 6.2, using Toyota’s published ratios. They are the gears for pulling away and for accelerating at low and moderate speed.
Is A High Gear 1 Or 5?
5 is the higher gear. Gear numbers climb as ratios fall: the GR Corolla’s 1st gear ratio is 3.538 and its 5th is 1.081, so in 5th the engine turns far fewer times for each turn of the wheels. 1st is the lowest gear.
Do Automatic Cars Have Gears?
Yes, most do. ZF’s 8HP automatic has eight forward gears built from four gear sets, with the computer choosing the gear. A CVT is the exception: per fueleconomy.gov it uses variable-diameter pulleys and a belt or chain instead of a fixed set of gears.
When Should You Downshift?
The owner’s manual of a 2025 Honda Civic Hatchback says the shift-down indicator will not prompt you to downshift for engine braking, so it is up to you when going downhill. It also says to shift down at the appropriate vehicle speed and to make sure the engine will not enter the tachometer red zone first.
Conclusion
Gears are ratios. Low gears multiply torque and cap road speed, high gears do the reverse, and the transmission type decides who picks the gear: you in a manual, the computer in an automatic, pulleys in a CVT, two clutches in a DCT. The published numbers show the pattern clearly, from a 14.36 overall ratio in the GR Corolla’s 1st gear to 3.11 in 6th, and from 4.714 to 0.667 across ZF’s eight gears. For anything specific to your own car, such as red zone speeds, engine braking and fluid, your owner’s manual is the authority.
- This guide does not cover transmission repair costs or rebuilds; ask a transmission shop for an estimate.
- It does not give a single recommended shift rpm, because that varies by engine and is set by the maker.
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