Where to find gear ratio on rear differential

Slide a floor jack under the rear of the vehicle and raise it until the rear wheels are off the ground. Four-wheel-drive trucks will have a ratio in the front axles differential that closely matches that of the rear axle.

General Motors rear end differentials are referred to by the diameter of the ring gear ie.

Where to find gear ratio on rear differential. On this episode of Budget Build Garage we show you how to easily find the gear ratio on any rear end that has a posi unit without taking anything apart. Turn the wheel TWO revolutions and count the number of driveshaft turns. The number of driveshaft rotations will help you determine your rear axle ratio.

For example if it turned 3 and a half times its a 3501 ratio. If it turned 4 and a quarter times its a 4251 ratio. How to Calculate the Rear Axle Gear Ratio Step 1.

Slide a floor jack under the rear of the vehicle and raise it until the rear wheels are off the ground. Crawl under the vehicle and locate the drive shaft where it attaches to the front of the rear axle. Place a 6 to.

Place a piece. You can typically find your RPO code on driver side door panel or glove box. General Motors rear end differentials are referred to by the diameter of the ring gear ie.

75 inch 85 inch 105 inch. Our experts will help you find the correct ring and pinion set for your particular application. Give us a call at 800-216-1632 to get started.

This video shows you how to locate the vehicle axle ratio code of your truck. So an easy way to determine your actual gear ratio is to check the tag attached to the differential cover by the cover bolts. On the tag there should be some numbering such as 354 or 373 either of those numbers will give you the stock axle ratio.

How to Find Out the Gear Ratio With the VIN Number by Jesse Dempsen. The vehicle identification number VIN is a 17-digit code that is used to identify and track every automobile produced. Each number and letter contained within a VIN reveals information.

To find the axle gear ratio of any GM vehicle locate the RPO sticker typically located in the glove box and write down any codes starting with F G or H. Then find those codes in the table below. Enter the number of teeth on your ring and pinion gear set to find the gear ratio.

Ring Gear Pinion Gear Ratio Find all of the gear ratios available for your vehicle in our Application Guides or call our staff of differential experts at 800 510-0950 for LIVE help. Part 4 of 5. Determining a more accurate gear ratio Step 1.

Place the oil catch pan under the rear differential cover. Remove the bolts that hold the rear differential cover on. Use the appropriate socket and ratchet.

Remove the rear cover and allow the oil to drain. Rear-End Differential Gear Ratio Calculator. Enter the maximum potential safe engine RPM.

Enter the tire size diameter and the target vehicle speed in MPH. Click Calculate Gear Ratio. The value will be returned in estimated differential gear ratio based on the entered values.

Follow Us on Flipboard. Four-wheel-drive trucks will have a ratio in the front axles differential that closely matches that of the rear axle. Unless the trucks window sticker lists an optional axle ratio it will come.

Turn the raised wheel it should turn fairly easily and count the number of turns of the propeller shaft. With one wheel on the ground and one being turned the ratio will be turns of the propeller shaft divided by the number of turns of the wheel times 2. The wheel is turned exactly 20 revolutions.

The BOM will identify the model number the gear ratio the type of differential and all component parts. Traditional BOMs are 6 digits followed by 1 or 2 digits and start with the numbers 60 or 61. On some tags the first 2 digits dont appear on the tag but they must be used to identify the axle.

However you will also find the gear ratio on a label on your rear axle if it has not rotted awayfallen off and on your front as well if youre have a 4x4. The front axles label is more protected and more likely still intact. Rear bottom of the pumpkin in the case of the front.

Heres an example from a 2013 Ram I used to have and you can see it says 355 meaning it had a 355 gear ratio. To find a trucks axle ratio check the exterior of the differential that is the device attached to the axle that lets the wheels turn at different speeds to see if it has a sticker displaying the ratio. One way to calculate gear ratio is to put your vehicle in neutral and raise the rear wheels off the ground by sliding a floor jack under the rear of the vehicle.

Locate where the driveshaft links to the front of the rear axle and rotate the tire to make one complete revolution.