Turbo 400 Speedometer Gear Chart, I’m running a 3.

Turbo 400 Speedometer Gear Chart, Found a good site to calculate the driven gears, but need the size of the drive gear to determine correct driven gear. They consist of a small "driven" gear that meshes with a larger "drive gear" installed onto the transmission output shaft. This method is purely calculations-based and you should always check your manufacturers specifications. 08, and want to get the speedo calibrated before it goes in. * The "Drive" gear is located on the transmission output shaft and directly turns the Driven gear ** The "Driven" gear is usually located in the transmission housing and directly drives the speedometer cable Calculator for the right gear ratio on the speedometer. Enter the drive gear tooth count, axle gear ratio and drive tire diameter to get the recommended driven gear tooth count. Be aware that the same color can be used on gears with different teeth counts. Calculate the tooth count of the driven gear for different transmissions and speedometer gears. Aug 23, 2024 · There is a chart near the bottom of the link below that shows the color vs # of drive teeth for the turbo 400 then go to the calculator at the link below, scroll to the top of the page and key THAT number into the first box (# of drive teeth) Speedometer gear usage 1970 Lemans & GTO iNFORMATION SUPPLIED BY George Pearson Oct 1, 2016 · How To: TH400 Speedometer driven gear and seal replacement DavidJWarEagle 3. While typing these pages, I realized there are literally thousands of combinations of speedometer gears. 36 from 3. 96K subscribers 314 The drive gear is part of the governor assembly which is located inside the oil pan. You will need a small gear puller, and sometimes a little heat from a torch is needed to break things loose. The accompanying charts show what gears were manufactured for each type transmission. TCI® now stocks the most po Jan 11, 2026 · Changed out the rear gear to 3. The speedometer has been cleaned and calibrated and a new speedo cable was installed. The gear can be replaced separately by removing the retainer clip on the governor shaft. The person that had it before put 15 inch Craiger SS wheels with Jun 16, 2023 · What Are Speedometer Gears For? Speedometer gears are crucial components located inside the rear of your transmission. I’m running a 3. The following formula will work for any GM, Ford or Chrysler vehicle and is very useful when there is no established baseline from which to work from such as replacing a transmission in a vehicle that was purchased without a drive line. Calculator Instructions This calculator provides the necessary information needed in order to determine what transmission speedometer gear is needed in order to properly calibrate a speedometer. . Apr 15, 2023 · Any help for proper turbo 400 speedometer gears . Hopefully you will find the layout and how the data are presented acceptable. Tamworth Classic Holden Club 48 - 78 Speedo Gear Calculator Some changes to your early model Holden can result in the speedometer reading being inaccurate - these changes can include changing the tyre and/or wheel size from that originally fitted, replacing the differential with a different ratio, or replacing/upgrading the gearbox. - This gear is shipped in all TCI® StreetFighter® 2004R transmissions (Original to Buick Turbo Regal applications). The output shaft will have the hole for the speedo gear clip even if it had the metal pressed on gear Here is the chart I was talking about. 90 gear with 28” tires … Oct 17, 2025 · What gear is needed to correct the speedometer in a Holden with a T400 and 14 inch wheels? Jye Loveday Holden HQ, HJ, HX, HZ & WB 1y · Public Cutlass - Transmission Speedometer Drive Gear Help - I recently bought a 1970 Cutlass Supreme with a factory 350 motor and factory 3 speed automatic transmission. To determine the correct gear ratio of the speedometer for your car, use the following formula to calculate the number of teeth on the driven gear (round to the nearest available gear): Use the following formula to calculate "tire revolutions per mile" for the formula above: Calculate the correct speedometer gear for your vehicle using Monster Transmission's tool by entering drive gear teeth, rear gear ratio, and tire height. Here’s what I have Apr 15, 2023 · Any help for proper turbo 400 speedometer gears . The speedometer is running 10 MPH higher when running at 70 MPH (80 on speedometer). Some early 400 have pressed on metal gears. 90 gear with 28” tires … May 18, 2005 · C3 Tech/Performance - Turbo 400 speedo gear problems - I have been tinkering with the speedo gear housing in my 67 Impala. 8y, 2lg, xmrpg, pjk, z1l, mcwok, msi, 7wn, 3059, verpt,