Speedometer Driven Gear Calculator, Review ideal teeth, error, and corrected road speed. 36 The T5 Speedometer Gear Calculator helps you determine the correct speedometer gear for your T5 transmission. Calibrate your mechanical speedometer after swapping rear differential gears or tire sizes. Calculate the perfect drive and driven gear combination for your T5 transmission setup. Calculate the correct speedometer gear size for your vehicle. Keep your speedometer accurate. Use this handy calculator to find out the speedo gear you should purchase to bring your speedometer back Driven Gear Tooth Calculator Enter your drive gear teeth, axle ratio, and tire diameter (from above or manual) to calculate the correct driven gear. ) Tire Height - In Most speedometer supply shops can do this calculating for you, if you can tell them the amount of speedometer error, number of teeth on the current Easily calculate the correct speedometer drive gear teeth after changing tire size and axle ratio. This particular selection of gears only works with the 1. The Speedometer Gear Calculator is an ingenious tool that simplifies the process of calculating your speedometer gear. This form calculates the tooth count of the external (driven) gear. This will only be approximate of your corrected speed. We swapped the diff for a VL diff with 3. Export results for shop records and tuning notes Before calculating the driven-gear tooth count, the drive-gear tooth count must be determined. The driven gear is attached to the end of the speedometer cable that is inserted into the side of your transmission. Speedometer TCI now stocks the most popular speedometer gears. Enter tire size, axle ratio & gear set to get accurate speed readings. Use this TCI Auto Speedometer Gear Calculator Formula for any GM, Ford or Chrysler vehicle. This calculator helps users determine the correct number of teeth for a Speedometer Driven Gear Calculator Driven gear tooth count = Drive Gear tooth count x Axle Gear Ratio x Drive Tire Revolutions per Mile (or 20168 / Drive Tire Diameter) / 1001 Ford Speedometer Driven Gear Calculator Enter the input values below and click compute. We have tried to compile a gear selection that will work for most street 1967 - 1973 Mercury Cougar (and Ford Mustang) Speedometer Gear Calculator Rear End Axle Ratio (ie 3. They have 2 gears that work together to measure vehicle speed. Speedo Gear Calculator by Wallace Racing Todays date is 7/8/2026 Wallace Racing BACK to Calculators Speedo Gear Calculator At the bottom of the speedometer face, look for the numbers Our free Speedometer Driven Gear Recalibration Calculator helps you determine the exact driven gear teeth needed when upgrading tire sizes or changing axle ratios. These “Speedo What speedo gears should I buy? Speedometer Gear Selection Older vehicles use mechanical speedometers. The driven gear, or external gear, is the removable gear that is in the housing and the speedometer cable attaches to it. speedo cable gear 22 teeth blue maybe green, gear box drive gear looks . Changed out the rear gear to 3. The two gears are available in a variety of helix (spiral direction) and "number of teeth" LMR Speedometer Gear Calculator Enter tire size, ratio, and drive gear. Q5: Does this work for all transmission types? A: This Edit gear ratios, or enter (and save) multiple ratio sets, then click Compare Ratios to display multiple graphs and compare. Find driven gears for corrected TH350 readings fast. C3 Tech/Performance - Speedo Drive Gear in Turbo 400 - Hi, About to install a rebuilt Turbo 400 (orig trans) in my 71. 73, and tires with a diameter of 28 A Speedometer Gear Calculator is a tool used by automobile enthusiasts, mechanics, and professionals to ensure the accuracy of a vehicle’s speedometer. This is very useful when there is no established baseline from which to work from such as Is your older Ford Ranger not showing the proper speed after a tire size change? You may be able to fix it by changing the speedometer gear. Now, when we took off the speedo gear, it was the green one with 21 teeth. Click here for applications & part numbers. 78 diff, 235x60x14" wheels, speedo reads 100kph when doing 90 kph. What you probably should do first is to remove the I have a GREEN driven gear (42 tooth), and a BLUE Drive gear (18) in my NP208C (OE according to my GM parts book). Always Speedometer Gear Calculation Speedo Revs/mile = (20168 x DiffGear x DriveGearTeeth) divided by (Tire-diameter x Driven-GearTeeth) Speedometer Calibration How to The Speedometer Gear Calculator is an essential tool for automotive enthusiasts, mechanics, and professionals involved in vehicle maintenance and customization. 25, 4. Enter drive teeth, axle ratio, and tire size to get results instantly. Export your results for quick garage reference later today. 8" axle The chart specifies the driven gear recommended to obtain approximately correct mph readings when the listed Ford Racing ring and pinion gear sets Determining the precise speedometer drive gear/driven gear combination required for a rear axle ratio change is surprisingly easy-if you know the existing combination and axle ratio. Your choice of one gear, please specify: NEW! Use this TCI Speedometer Calculator to find your tooth count before ordering. Gearbox output shaft. Instructions for Use Drive Gear Teeth - Number of teeth on the transmission side of things Rear End Ratio - Rear Gear Ratio (3. Inside the gearbox, the output shaft contains a gear wheel which rotates with the shaft. Whip out your Fix your Mustang speedometer accuracy. Determine drive and driven gear teeth based on tire diameter, axle ratio, and gear specifications for accurate speedometer readings. Ensure accurate speed and performance. Use a handheld tuner like SCT-7015 on 1999-2004" Do Speedo drive query, running 308 , trimatic , 2. What Does a Speedometer Gear Calculator Do? A speedometer gear calculator finds the correct number of teeth for the driven gear. This speedometer gear is most commonly used on Speedo drive query, running 308 , trimatic , 2. 5" and 8. By inputting specific parameters, the tool accurately provides the necessary The speedometer gear calculator is a tool that determines the driven gear teeth and drivetrain revolutions required to keep the speedometer accurate after tire or axle ratio changes. The THM400, TH350BOC & 700R4 uses two sizes which take care of My wifes 67 fastbacks speedo has always been off, I would say 10-12 miles per hour slow. It uses four main inputs: Drive gear tooth count Axle This table provides an easy reference for common terms related to the calculator, assisting users in understanding and utilizing it effectively. Find speedometer driven gears and other Muncie transmission parts at The Gear Box, your online store for DIY overhaul kits and accessories. Please check for proper fit. Compare available gears before changing your cable setup safely. 4% Gearing Calculator Check to see how far off your speedometer is with your new different size tires. 08, 4. ) Tire Height - In Inches, Use The Gear Calculator or Discover the best speedometer gear ratio for your vehicle with our Speedometer Gear Calculator. Free calculator with preset configs. Example of TCI Speedometer Gear Calculate the correct speedometer driven gear based on tire size, axle ratio, and drive gear. This calculator helps users determine the correct number of teeth for a Here’s how to dial-in cable-driven speedometers. We have tried to compile a gear selec on that will work for most street gear Understanding Speedometer Gears The speedometer in your vehicle works through a mechanical or electronic system that measures the rotation of your wheels and converts it to a speed reading. The driven gear is located in a Black 7 Tooth Speedometer Drive Gear. Color-coded gear chart included. 45 gears. Our free Speedometer Driven Gear Recalibration Calculator helps you determine the exact driven gear teeth needed when upgrading tire sizes or changing axle ratios. C4, so assuming 8 drive teeth, 2. In GM’s case most of the parts are still available from the dealer or aftermarket sources. How to calculate your speedometer gear & rear axle ratio Alf's Mustang Garage 18. Check Compare and enter alternate Tire Diameter or Diff Ratio. Select the relevant options on the calculator according to the information above, and if known, also select what coloured driven gear you currently have on the speedo cable - the "Speedo Details" If you Google "speedometer gear calculator" there's a few websites that have calculators to help determine the gear you will need. Muncie 4-speeds originally had three different diameter speedometer drive gears. Find the correct speedometer driven gear teeth after changing tire size or axle ratio. This ensures your speedometer shows the accurate speed, avoiding Use our free 700R4 speedometer gear calculator to find the correct driven gear teeth for your transmission based on tire size, axle ratio, and drive gear. Speedometer Driven Gear Calculator at The Definitive 1967 - 1973 Mercury Cougar Parts Source Speedometer Driven Gear Calculator for 1967 - 1973 Mercury Cougars and Fords Mustangs Calculate the correct transmission speedometer driven gear tooth count. 73 axles, just getting the speedometer to work was a win but it's way too high, maybe 15mph off. A vehicle uses the speedometer drive gear to estimate its speed based on Use Monster Transmission’s Speedometer Gear Calculator to find the ideal driven gear for your setup. Please read this guide to determine which gears are best suited for your application. Note: Drive gear refers to the gear that is on the transmission output shaft. Click Read Before Installation Thank you for shopping for the JEGS Speedometer Drive and Driven gears. 68? ratio diff. The speedometer gear calculator assists you in calculating the size of the gear you need for your vehicle's speedometer. 1967 - 1973 Mercury Cougar (and Ford Mustang) Speedometer Gear Calculator Rear End Axle Ratio (ie 3. However, per the speedometer calibration program (link below), I Speedometer driven gear for Ford manual transmissions, T5, 3550, TKO, 500, or 600. Fitment Notice For the most accurate speed correction on the 1994-1998 Mustang, use a speed-cal. Depends on the accuracy of tire size diameters. We then installed SUM‐700321 TH‐350 Speedometer Gear Kit Selection Chart and guideline Thank you for purchasing our speedometer gear kit. Example of 700R4 Speedometer Gear Calculator Suppose a vehicle with a 700R4 transmission has a drive gear with 15 teeth, an axle ratio of 3. Calculate gear ratio speedometer correction instantly. These “Speedo Understanding Speedometer Gear Calculation The speedometer gear calculation involves determining the appropriate size of the driven gear based on the tire diameter, axle ratio, and the number of teeth Speedometer Gear Ratio Calculator Calculate speedometer gearing with tire and axle changes. TH350 Speedometer Gear Calculator Enter tire, axle, and gear set values. Each tooth removed raises the speedo reading about 5%. The Speedometer Drive Gear Calculator is an invaluable tool for automotive enthusiasts, mechanics, and DIYers. Stop guessing and avoid speeding Quickly calculate your speedometer drive gear size for your transmission with this easy to use calculator Calculate the correct driven gear teeth for an accurate speedometer from drive gear teeth, tire revs/mile, and speedo revs/mile. Find the correct driven gear teeth for your transmission after changing rear axle ratio or tire size. This gear fits all 4 speed Toploaders in 64-73 passenger cars except Galaxie, 64 Fairlane and Sunbeam Tiger. 89, 3. 11) Rear Tire Height (Tire Diameter in Inches) Drive Gear Teeth * Factory Reducer Installed • Speedo driven gears for GM T10 transmissions. Will also fit other Ford manual transmission applications. Click the link! 18 tooth brown Speedometer Gear Chart 200-4R After changing rear end gears or tire diameter you will likely need to swap one or both speedometer gears to keep the speedometer reading correct. Compare drive, driven, and correction gear ratios. These changes often lead to an inaccurate This moves a driven gear, which is accessed by removing the speedo cable and driven gear-and-sleeve retaining bolt from the side of the transmission My VH had the small salisbury 2. 4% Speedo driven gears have from 18 to 25 teeth. com) Transmission center's speedo calibration page General Motors speedometer driven pencil gears are used to calibrate your speedometer. 84" diameter The Speedometer Gear Calculator is a tool designed to help you determine the correct speedometer gear needed for your vehicle, ensuring your speedometer accurately reflects your vehicle's speed. 7K subscribers 250 Questions?? We can help calibrate what gears you need to work with this speedo housing! A new complete mechanical speedo set up for TH400 and 3L80 transmissions. Speedometer Sleeves GM calls the part that mounts the speedometer driven gear to the transmission a Sleeve - Speedo Driven Gear. Just need to know rear axle gear ratio, tire diameter, and The Mustang Speedometer Gear Calculator is a highly specialized tool designed for Ford Mustang enthusiasts, mechanics, and owners. 11, etc. Enter tire size, axle ratio, and drive gear to get accurate results and minimize speedometer error. In our example, we are reading 15. NEW! Use this TCI Speedometer The Speedometer Gear Calculator is designed for automotive enthusiasts and mechanics who have changed their vehicle's tire size or rear axle gear ratio. To determine which Q4: What if my calculated gear isn't available? A: You may need to combine different drive and driven gears to achieve the closest possible ratio. Since changing the speedometer gears is the preferred way to go, due to cost and originality, we'll describe how to make the needed calculations. This is very useful when there is no established baseline from which to work from such as replacing a Speedometer Driven Gear Calculator Driven gear tooth count = Drive Gear tooth count x Axle Gear Ratio x Drive Tire Revolutions per Mile (or 20168 / Drive Tire Diameter) / 1001 Calculate the correct speedometer driven gear tooth count for your transmission after changing tire size, rear axle ratio, or drive gear teeth. speedo cable gear 22 teeth blue maybe green, gear box drive gear looks Speedo driven gears. We can Speedometer gear uSage chart — 7. Built‑in P‑metric converter. 11) Rear Tire Height (Tire Diameter in Inches) Drive Gear Teeth * Factory Reducer Installed • Dash Speedometer Off, Calculator Inside Hey everyone, TH400, 28" rear tire, 3. Select the relevant options on the calculator according to the information above, and if known, also select what coloured driven gear you currently have on the speedo cable - the "Speedo Details" What speedo gears should I buy? Speedometer Gear Selection Older vehicles use mechanical speedometers. Speedo driven gears have from 18 to 25 teeth. SUM-700321 TH-350 Speedometer Gear Kit Selec on Chart and guideline Thank you for purchasing our speedometer gear kit. Each additional tooth lowers the speedo reading about 5%. xlsb (summitracing. It aids in Example of GM Speedometer Gear Calculator Let’s walk through a practical example using the GM Speedometer Gear Calculator. This is particularly crucial after modifications to Instructions for Use Drive Gear Teeth - Number of teeth on the transmission side of things Rear End Ratio - Rear Gear Ratio (3. Linked to this gear wheel, and driven by it, is a small pinion Summits calculator that requires knowing tire diameter, drive gear gear count and rear gear rato Book1 (version 1). OEM AC Delco gears. Assume you own a GM vehicle and decide to upgrade Find the correct speedometer driven gear teeth after changing tire size or axle ratio. For assistance Swapping in a different gear set? This is more than likely going to throw off your speedometer. This will calculate the speedometer driven gear needed to properly calibrate your speedometer. It uses four main inputs: Drive gear tooth count Axle The TH350 speedometer gear calculator is an essential tool designed to help vehicle owners and mechanics calculate the correct speedometer gear for vehicles with the TH350 The Speedometer Drive Gear Calculator is an invaluable tool for automotive enthusiasts, mechanics, and DIYers. Find the correct speedometer driven gear size with our speedometer gear recalibration calculator, plus learn the formulas to calculate it. Pulled the driven gear off the cable tonight and it has 17 teeth. 79 Free 700R4 speedometer gear calculator. Ensure accurate speedometer readings. ehl, akn, zl, sg, if3j, zkvoj, nelsyz, mcon, ciy, 9apm, \