Rear End Gear Ratio Chart
00 as this is the typical 4th gear ratio of most 4 sp and 5 sp manual transmissions. The reason it does not have this feature is that the gear ratio is also the tooth count ratio (of the two gears), and that is a value that the user has to enter. In this case, it is an 8" ring gear. the pinion. Limited Slip. Try our simple and easy to use Gear Ratio Calculator to quickly find the correct gear ratio for your differential. The differential gear experts at Ring and Pinion Service are also a great resource and would be happy to recommend and install the ideal ratio for your needs. There's no question, the easiest way to identify the axle and gear ratio in your truck is from the door sticker. The second and third digit, both numbers "29" refer to the gear ratio. 55 3800 FORD REG 1991 25 4. This calculator will provide the speed of the vehicle based on the transmission gear ratio, the engine RPM, the tire height, and the ring gear and pinion gear ratio in the rear end axle differential housing. For the Tire field, enter your tire diameter in inches. 73's in every gear other than 1st, amd even 1st is really close. The second is used on some 6cyl and all 8cyl cars and is an 8" ring gear removable carrier axle. In-depth knowledge breakdown of the various components of a car. Drive Gear Teeth - The Number of teeth for the transmission; Rear End - Rear Gear Ratio (3. My truck has the 3. and five speed manual. 23 gear ratio in itdoes any body know if thats rarer to have than the 2. 00 as this is the typical 4th gear ratio of most 4 sp and 5 sp manual transmissions. I picked up an 8. In a simple differential, it is just the ratio of teeth on the ring gear to the number of teeth on the pinion gear, but in a double-reduction rear end the math gets a little more complex. Also see AMC Automatic Transmissions Chart. two speed rear ends use a planetary to reduce the input gear from the main HIGH ring gear reduction through planetary reduction and out the axle shafts. The use of any additive in locking rear axles (G80) is not recommended. 10) the computer program would not allow it. Our easy to use calculator gives you a wealth of information when searching for your rig’s best gearing—three recommended gear ratios! Once your information is entered and calculated, we recommend the best gear ratios for fuel economy, towing and a balance of both. PROFESSIONAL & SPORTSMAN. It is also the same letter that Volkswagen uses on the end of the ring & pinion part number to identify that gear ratio. 8" Reverse IFS and adjust your truck's final drive ratio for improved power or to get rid of sloppy shifting and sluggish driving that's caused by throwing larger wheels and tires. Mark the bottom of the driveshaft and the bottom edge of the passenger side tire. Rear Axle Assembly Codes The rear axle ratio may be determined by finding the two- or three-letter serial number prefix in the following table. 23 Ratio GU6 Axle, Rear 3. 200Cover Bolts: 10Ring Gear Bolts: 10Spline Count: 28Dropout: FalsePinion Support: FalseCa. a) The capital letter which identifies this gear set is supposed to be stamped with the serial number of the transaxle on the outside of the case. 25 axle looks like this (12. Go Kart Gear Ratio Tool. 73 3800 FORD REG 1991 17 3. 56 gear ratio with 35″ tires. Traditional BOM’s are 6 digits followed by 1 or 2 digits and start with the numbers 60 or 61. Spicerparts. jeephut gear ratio and tire size calculator When you change your tire size you need to make sure you have the right gearing to get optimal fuel economy and power. I'm looking for a second gear ratio around 1. Axle ratios may be expressed in notation as something along the lines of "3. Mustang II Axle Identification The Mustang II utilizes two different style rear axles. Enter the tire size diameter and the target vehicle speed in MPH. Drive Gear Teeth - Number of teeth on the transmission side of things Rear End Ratio - Rear Gear Ratio (3. Axle ratio can be used in reference to either the front or rear axles, depending on if the vehicle is front wheel drive, rear wheel drive, all-wheel drive, or four-wheel drive. The E-Type is not going to hit 274km/h irrespective of gearing): E-Type Differential Ratios. How to Find Out the Gear Ratio With the VIN Number by Jesse Dempsen. Example a 700R4 transmission has an overdive ratio 0. housing identifying to gear-set inside. In the end, it's easy to see that mistakes in gearing can craft a truck load of trouble. 08 are the ring and pinion gear ratios in the rear axle. Enter the maximum potential safe engine RPM. To find the output torque and speed of a gear increaser, use the equations: Ouput Torque = Input Torque x Ratio of Gear Increaser. This is the ratio of gears in the rearend (differential) that you may have heard of in the numerical terms 2. Best known for our huge selection of ring and pinions, G2 also produces axle shafts, locking differentials, hubs, housings and even complete axle assemblies. We need to understand final drive ratio to calculate our speed at RPM. The Chevy’s rear axle code contains information on the vehicle’s gear ratio, date of manufacture and the rear axle assembly plant. For example, a Camaro that has decent acceleration with a set of 26-inch tall tires and 3. One revolution of the rear wheels usually moves a 1965 to 1973 Mustang a little over 6 feet. Currie 9-inch rearend with direct bolt-in fit for 1964 thru 1966 Mustang and Cougar vehicles. Rockwell Differential ID Profile & Information. Axle Decoder Chart Code Ratio Capacity Maker Type Yr 12 2. GM/CHEVROLET FINAL DRIVE RATIOS It is the gear under your seat that counts. The 1962-63 serial numbers are located on the front, right side of the differential carrier. With that gear, the 1st launch will be like having a 4. To do another, enter a new set of values. A huge thank you to 1 Wild R/T for suggesting it. This calculator will help you compare the total cost of ownership of an UltraShift HV equipped truck compared to an Allison Automatic transmission equipped truck. Changing Rear Gear Ratio?, Need to Change Speedometer Gears. Listed 1967 “AQ” and “AR” codes & ratios may only have been used early in the 1967 model-year, or not at all. This will help you pick the right size tires, transmission and gear ratio combination for your classic. Which, if you don't know the history of your truck, it's not a bad idea to change the gear oil, and identify which carrier you might have when the cover is off. The Mack Differential wholesale warehouse, all models and all ratios are in stock and ready to install. Here is a cgi I wrote to do gear ratio calculations. Click "Calculate Differential Gear Ratio". I need the gear ratio THANK YOU. Re: How do you find your gear ratio? I could REALLY be wrong here, but I think with your engine, and the year, the only axle Ford put on a stroker, F250, was a 3:73. Definition: gear ratio n. Our Mission is to "Keep Hot Rodding Alive" - We Promote and Support Real Deal, Old School, Traditional, Bad-Ass Hot Rodding by Providing Informative and Motivating Content along with Our Team's Experience and the Collective Know-How of Our Internet Family of Friends, Fans and. Using the chart, first determine what your original gear ratio and tire size are, then follow the lines to find your approximate RPM at 65 MPH. Use this gear ratio calculator to see what ring & pinion gear ratio will be right for you after a tire size change. A very common mini bike ratio is 11-12 teeth on the clutch, and 72 teeth. Gear ratios are tricky to understand, so let's talk about some basics and see if we can sort some things out. Drivetrain com Discount Automotive and Truck Parts Ring and Pinions, Transmission and Transfer Case Parts, Overdrives, Positractions, Towing products Free technical support 800 216 1632. Rear axles can be identified by a code stamped on the front of the right axle tube about 3 inches out from the carrier and 30 to 45 degrees above horizontal or on a metal tag attached to a rear cover bolt. 01 different. It is based on the above formula. I find myself looking up gear ratios for Subaru Models a lot, so I figured I'd post it here as a reference for everyone! I got this information on NASIOC posted by the user North Ursalia. About BoostTown. What does the Rear Differential do?. Last but certainly not least, you need to consider whether your vehicle will benefit more from a performance gear style or a pro gear style. ) Tire Height - Please use Inches when measuring. 05 tire rotations for 2 engine rotations, which figures out to a rear end ratio of 3. You could also jack it up and do the wheel revolution, driveshaft revolution comparison, but that's not convenient and it's imprecise. 73 or the 3. At least I used 3. In addition to supplying increased torque for towing and motor homes, these gears are an excellent alternative to steep rear end gears for street driven performance vehicles and low RPM, high torque race engines. The higher gear ratio the quicker acceleration you get but lower fuel mileage. Using the charts below, you will be able to learn alot about the rear differential in your classic full size Chevy. Take a look at the Ford's towing guide chart below. Edit by Ed Quinones on 10-7-05: I used to own a 99 Prerunner ext cab 2. The five speed option is for the last gear of a transmission greater than four speeds. Differential Gear Ratio. Re: Rear End Gear Ratio 08-24-04 11:56 PM - Post# 501729 In response to Edispets I did a "Gear Charts For My 1965 GMC 2500" webpage, it also has some other info about figuring gears and hph with a link to a site you can just plug inyour numbers and get your speed. High rpms get to be annoying after a while [QUOTE=rod7515] What r the costs of changing the gear ratio in a vette. Not all applications will have one of these codes but when they apply, they will be listed in addition to an axle code found in the main RPO axle code list below. Dodge Ram 2009-Present: Gear Ratio Information. You are at: Home » Main » How to choose rear end gears the right way. Ring-and-pinion selection made easy! Save yourself the headache and let us figure out your ring-and-pinion gear ratio! Just type in your info (example: 5000 RPM), press calculate, and you'll get the right ratio without the guesswork. To determine your gear ratio, simply divide the rear axle sprocket by the clutch sprocket, so in the case of the above example, 60 divided by 12. The gear ratios can remain as is for most of the other adaptions. 2 ring gear. Standard Rear End's as Delivered From The Factory 1969-1989 : 240Z 70-73 MT (3. 17:1, depending on the truck class, make and model, and rear-axle capacity. Differential Ratio x Transmission Ratio (ie; 4. 25" master install kit is used. Which, if you don't know the history of your truck, it's not a bad idea to change the gear oil, and identify which carrier you might have when the cover is off. How to Calculate Engine RPM vs. Access Optimum Transmission Gear Ratios Calculator RICHMOND is the leading manufacturer of professional quality, hi-performance ring and pinion sets. I am curious if any one has looked into thier axle codes and know what the ratio is on theyre truck?. gear ratios & tire sizes xls. Intro to Physics of racing Series. 82 gear or Set # 13 for your 1. It is complicated. 00 on the 4th gear, 0. Does anybody know the stock ratio? If you know the answer or where I could find it, please post it. Gear ratio will depend on what your plans are with the truck (IE: trail rig, DD, etc. Gear Ratio Calculator. I have a 1972 chevelle malibu with a 350 and a 4-speed, but I don't know what the gear ratio in the rear end is. Why are the tow ratings for a given vehicle different based on rear axle gear ratios? For instance, I have a 2002 Ford Explorer V-6. This was done as a direct result of the 1973 oil crisis. 42 rear axle. 73 gear ratio with a limited slip in a 8. A good way to calculate this is to multiply. HOW DO I FIND OUT WHAT GEAR RATIO MY 03 NISSAN FRONTIER HAS? - Answered by a verified Nissan Mechanic Rear end bad, ran without oil, need complete rear JA: When. 93:1 gear ratio. 25" long pinion gears are also compatible with the Ford 10. Mark the driveshaft somewhere you can see it from a safe area. If you have ever wondered what the gear ratio is in your rear-wheel drive vehicle and. When the gears came out, sure enough, they were 3. Changing to a 3. What are the benefits of a rear gear swap? Changing the rear end gear to a numerically higher (like going to a 3. It had a 302 V8, 4-speed manual overdrive, and a 3. This is the "pumpkin" only, not the axle housing. Go Kart Gear Ratio Speed Calculator (MPH). Raise one rear wheel. Mark the raised wheel and t. Dana 44: These are the beefier axles found on the rear of all Wrangler models now with either a 3. 91 gear ratio, at least for the 5sp. First gear MT improvement to JL would make the 3. It should work. Gearing is what you are buying when you purchase a Gear Vendors Under/Overdrive. You might also want to read How Gears Work to find out more about different kinds of gears and their uses or you can learn more about gear ratios by visiting our gear ratio chart. Example; the original rear pinion gear on my k10 exploded, and it was cheaper to buy a parts truck with a good axle than to. 3+ is green, 2-3, blue, and below 2, red. This explains why two gears, one half as big as the other, have a gear ratio of 2:1. 1 - This is a retrofit gear to allow the speedometer to function with 3. Later in other products and I've heard that jeep used them until mid eighties. The front axle should have the same gear ration as the rear. 1st gear ratio: 3rd gear ratio: Rear axle ratio: Speed (mph):. 6 ratio and will probably be melted from all that extra torque. J55 - Heavy Duty. For instance, if the rear end ratio of your car is high, it will accelerate much faster but its top speed will be reduced. Enter the maximum potential safe engine RPM. T he following pages provide a scientific glimpse of racing and should be enjoyed by Engineers and a must read for all students in the FSAE program. If your front axle only has 4. 28 to 1? Also curious if anybody knows the axle ratio for the tacoma's equipped with automatic tranny's? Thanks for the help. charts, and illustrations to give simple step-by. The following speedometer drive gears and driven gears are available for the 700R4 / 4L60 transmissions. Rear End Ratio @ Desired MPH: Tire Diameter (Height) in Inches: Over Drive Ratio (1 for no OD) Estimated Rear End Ratio. The term refers to the gears in the truck's differential, which is a mechanical device that links the rear. High Performance Circle Track and Oval Track Race Parts for Sprints, Late Models, Modifieds and Street Stocks. The code can be found just to the right of the word final, scroll down to see pictures. Remanufactured and Rebuilt Engines for Cars and Trucks. 58 gear set and a 2 pinion. Spicerparts. The car’s rear end ratio decides the primary usage of the engine’s torque. The two axles are easy to tell apart. 10 limited slip. 91:1) compared to the 2016 Chevrolet Colorado's six-speed auto transmission gear ratios and axle. By Tim Palmer, Green Country Corvair Group. Rear end gears are EXTREMELY important for how a car performs. 55 5300 FORD REG 1991 35 4. There are 60 choices for the 2005 Chevrolet Silverado Rear Axle Assembly !!! Choose Your Option. 55, it if was 4x4 it had a 3. 73 to one, and 4. How does a gear ratio affect speed The gear ratio tells us how fast one gear is rotating when compared to another. For instance, if the rear end ratio of your car is high, it will accelerate much faster but its top speed will be reduced. To determine a rear axle sprocket from a given gear ratio with a given clutch sprocket teeth number, simply multiply the first number of the ratio by the clutch sprocket teeth number (is: 5 x 12 = 60). 25-inch oval. Tall (high) gears have LOWER numerical numbers such as 2. There IS a way you can identify which gear ratio the vehicle has. 38 to 1 ratio ring and pinion, you can cruise at 65 mph. This was done as a direct result of the 1973 oil crisis. 98 on the 1st gear, 1. Dodge Ram 2009-Present: Gear Ratio Information. 23 gear ratio in itdoes any body know if thats rarer to have than the 2. March - April 2003 Lane Racing And Rodding Article By Jim Kaekel, Jr. 6 to cooperate with my rear end gear and tire size, long story. I have the following information from the Chevrolet VIN Decoder. Step 3 - Select Rear End Axle Gear Ratio Mustang rear gears from 2. The chart below will help you to select the optimum gear ratio to bring the power and torque back to where you want them. Traction is affected by gear ratio. 00 rear end. If you are curious of how your rpms will be affected, use the following formula and plug in the numbers. Considering making modifications to your Jeep? Whether it is changing an axle or going with different tires this chart is helpful in finding the right Tire Size to Gear Ratio that you need to achieve the optimal performance for your particular application. A huge thank you to 1 Wild R/T for suggesting it. there might be another gear-set for H/O cars (just guessing). The second calculator allows you to actually input any EXACT transmission final gear ratio. I would stay with the 3:08, or maybe the 3:55but no more, unless you rarely go on the road with it. This tag will show what size axle and what ratio you have installed. 22 and in OD it'll be like having 2. This is the "pumpkin" only, not the axle housing. 42 Ratio G80 Axle, Rear Posi-traction (Limited Slip). 11 rear axle gear ratio, unless you plan to run full throttle stoplight to stoplight. September 13, 2011 March 11, 2012 phrog. Most cars and trucks with low rear end ratios will take a 15 tooth drive gear. 08 times for every one. The gear ratios for reverse are not provided. This is what I have and your code matches mine exactly. Rear Axle Gear Ratios. In addition to supplying increased torque for towing and motor homes, these gears are an excellent alternative to steep rear end gears for street driven performance vehicles and low RPM, high torque race engines. Differential Gear Ratio Calculators. 10:1, and so on. REAR SUSPENSION. I'm looking for a second gear ratio around 1. Calculates gear ratios, speeds, RPM drops, tire size. The addition of larger tires can greatly decrease performance and fuel economy. The common interpretation of final drive ratio for a quick-change rearend is the combined ratio of the axle ratio and the QC gear ratio. Certainly not the conditions for which the folks at Abingdon designed the TD or TF. Car in neutral (block the other wheels all around to ensure the car can't roll!). The 200R4 and 700R4 seem to be the swap of choice, provided you run a fairly stock engine. Our Differential Gear Ratio Calculator can help you select the correct gear ratio to maximize the performance of your vehicle. This would be 3. The BOM will identify the model number, the gear ratio, the type of differential, and all component parts. More teeth slow the speedometer down, less teeth raise the the speedometer. If you take a few moments to study the gear chart for your transmission and rear end ratio combination you will see why this product is so popular. ford driveshaft & differential choice parts interchange. If you are looking for help with restoring or hot rodding your chevy classic a good place to go for help is Chevy Talk my favorite forum is 1955-1957 ( Modified / pro street / show) forum. The fourth and final digit, "2". The best ratio is to have your engine run at the sweet spot RPM at the speed you will be running most of the time. 73 gear ratio with a limited slip in a 8. Why are the tow ratings for a given vehicle different based on rear axle gear ratios? For instance, I have a 2002 Ford Explorer V-6. As a general rule, when dealing with two gears, if the drive gear (the one directly receiving rotational force from the engine, motor, etc. if not I have other 9" info archived I can post. 92 gears, no towing package, but i also have the corporate axle, but i cant remember if it is 8. My question is what rear axle ratio should I go with? Here in CA the speed limit is 55mph when pulling a trailer and with my current truck I'm having to drive at 60mph to keep the engine from lugging in OD. These Dana 70 axles only came with 5. You would find that, because its diameter is one half of the circle's in the figure, it has to complete two full rotations to cover the same 4 inch line. 56:1, pick the ratio you currently have or are planning to install. DRAG PERFORMANCE CALCULATOR. 00-1 and i found one that is a stock 3. 10 bolt street gears are designed to withstand the rigors of everyday driving, as well as a weekend at the track. 25" master install kit is used. Example a 700R4 transmission has an overdive ratio 0. Definition: gear ratio n. Automakers Offer Variety of Axle Ratios There is good reason automakers offer a variety of different axle. A stamped steel cover on the rear of the center section can be removed for inspection and maintenance. There's no question, the easiest way to identify the axle and gear ratio in your truck is from the door sticker. In this case, it is an 8" ring gear. Hi, I'm new to this site, and I'm thinking about replacing my kingcab's 2wd rear axle assembly with a 4wd's, to reduce the ratio, for better towing, and bring my truck up some. 1580 t5300*< r3a) y35/, pa 17408 usa p-. 11 rear end in it, but not 100% sure of that. Lets look at these two perfectly rount gears. 08s, then the engine must turn 3. 364) (R180) 240Z 70-73 MT 5spd. So in order to get cars moving with 3. Note: If you have an automatic transmission your RPM will higher due to slippage in the transmission and the torque converter. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. 55, it if was 4x4 it had a 3. 29 axle, 78 to 82 V8 on all Foxes. Luckily, Late Model Restoration has put together this Mustang gear ratio to RPM chart to help identify which gears your Stang may have installed. The term refers to the gears in the truck's differential, which is a mechanical device that links the rear. Importance of rear end gearing: Rear end gear affects your cars acceleration, top speed and gas mileage. there might be another gear-set for H/O cars (just guessing). Effective & Equivalent Gear Ratios Based On New and Old Tire Heights & Original Gear Enter the New Tire Height, Old Tire Height, & Original Rear Gear Ratio, Then Press 'Enter' Key Effective Ratio = (Old tire height / New tire height) * Original ratio. Find Ring and Pinion Gears with Ford 8. Currie 9-inch rearend with direct bolt-in fit for 1964 thru 1966 Mustang and Cougar vehicles. If in doubt (and easy) the best idea is to check the diff. You can mark the driveshaft to help you count. High rpms get to be annoying after a while [QUOTE=rod7515] What r the costs of changing the gear ratio in a vette. Just in front of the transmission tailshaft housing is where the speedometer cable screws into the transmission. You can use it to try out different rear end gears and tire sizes. You can get a lot of different gear ratios if you want to rebuild a rearend. Importance of rear end gearing: Rear end gear affects your cars acceleration, top speed and gas mileage. For instance, if the rear end ratio of your car is high, it will accelerate much faster but its top speed will be reduced. com If you want to change the rear gear because you want more top end or you want to gear the car for a specific road course or. A commonly overlooked component of a vehicle's drivetrain that has a large effect on fuel economy is rear end gearing. No computer, charts or workbooks needed. HOW DO I FIND OUT WHAT GEAR RATIO MY 03 NISSAN FRONTIER HAS? - Answered by a verified Nissan Mechanic Rear end bad, ran without oil, need complete rear JA: When. It is also the same letter that Volkswagen uses on the end of the ring & pinion part number to identify that gear ratio. 58 gear set and a 2 pinion. To allow for the different gearing, the Dana 61 had a greater pinion offset. The effective multiplier of the stock M5 is (4. 1580 t5300*< r3a) y35/, pa 17408 usa p-. 10's in 2nd 3rd 4th. The second calculator allows you to actually input any EXACT transmission final gear ratio. Axle Ratio Drive Gear Teeth Driven Gear Teeth or 4. 55 3800 FORD REG 1991 25 4. For example, 41/10 gives you a 4. However, if you don't have the locking rear then you should have 4. 10 rear gear ratio and also use a Dana 44 axle in the front with either a 3. Use our simple Gear Ratio Calculator to quickly find the correct gear ratio for your ring and pinion gear set. To do another, enter a new set of values. East Coast Gear Supply offers wholesale discount prices on Dana 60 gears, off-road ring and pinions, ring and pinion gear sets, master install kits, pinion kits, mini install kits, axles, ujoints, bearings, air lockers, triple drilled flange, diff housings, solid spacers and other Dana 60 performance parts and accessories for your Dana D60 differential on your Dana Chevy K30, K35, C20, C25. Rear End Conversions. 25" long pinion gears are also compatible with the Ford 10. I originally went with 3. Changing to a 3. We’ve assembled a variety of manual gear ratio charts for General. In addition to supplying increased torque for towing and motor homes, these gears are an excellent alternative to steep rear end gears for street driven performance vehicles and low RPM, high torque race engines. 8 final drive ratio change The most common swap on a Z3 is a e36 m3 back end giving you a 3. Most cars and trucks with low rear end ratios will take a 15 tooth drive gear. Re: How do you find your gear ratio? I could REALLY be wrong here, but I think with your engine, and the year, the only axle Ford put on a stroker, F250, was a 3:73. If you are looking for help with restoring or hot rodding your chevy classic a good place to go for help is Chevy Talk my favorite forum is 1955-1957 ( Modified / pro street / show) forum. Rear axles can be identified by a code stamped on the front of the right axle tube about 3 inches out from the carrier and 30 to 45 degrees above horizontal or on a metal tag attached to a rear cover bolt. About BoostTown. 50 rear end, it cruised effortlessly on the highway in OD and got 22 MPG. Tundra gear ratio? Jump to Latest I think my 03 with TRD has a 4. There are many other factors that affect the gear ratio and vice versa, including transmission type and individual transmission gear ratios, tire diameter, and torque converter stall speeds (automatic). 30 Final Drive Ratio Electronic Limited Slip Differential Rear Five-link independent with. Note: Ford 10. Both axles should be geared the same. you look at a chart of ratios for different size ring gears, you will that the front vs rear axle ratio difference is. Gear Ratio and Tire Size Calculator - 4x4 and Jeep Ring & Pinion When you change your tire size you need to make sure you have the right gearing to get optimal fuel economy and power. Does anybody know the stock ratio? If you know the answer or where I could find it, please post it. T he following pages provide a scientific glimpse of racing and should be enjoyed by Engineers and a must read for all students in the FSAE program. Colors group similar values. 73 open axle or 4. As long as there's less than a 1% difference between the ratios, they're considered "close enough". If you open the drivers door and look at the door jamb, you'll see a sticker like the one shown below: You'll see that the area labeled (F) is for the Axle Code. This is the "pumpkin" only, not the axle housing. 8-inch axle has the same ring gear mounting distance (see Chapter 7) for all ratios, just like the 9-inch. Edit by Ed Quinones on 10-7-05: I used to own a 99 Prerunner ext cab 2. Before we start, let’s identify the parts. How to Spec any truck with an Eaton Transmission; Select Desired RPM, Select Tire size and finally choose transmission gear ratio, 0. Mark the driveshaft somewhere you can see it from a safe area. 5" rear axles. Does anybody know the stock ratio? If you know the answer or where I could find it, please post it. Axle Spline:34. Vehicles without a rear differential, such as most go karts, allow both wheels to spin at the same speed. A metal date tag with the gear ratio is attached to two cover bolts. 55 for a 1999? The reason I'm asking is depending on what the axle ratio is help determine how big of a travel trailer we can buy. There are many other factors that affect the gear ratio and vice versa, including transmission type and individual transmission gear ratios, tire diameter, and torque converter stall speeds (automatic). 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):. 58 gear set and a 2 pinion. Examples of this would be a 3.