Rear End Gear Ratio Chart

You can use it to try out different rear end gears and tire sizes. He does mention pickups throughout so maybe there is credibility in that aspect. Login or register now to gain instant access to the rest of this premium content! Often overlooked, optional gear ratios play a key role in pickup truck performance. gear ratios & tire sizes xls. This chart has been revised with actual ratios. Everything else is interchangeable. 07 rear end gear = 3670 ft-lb. Chevy 10 Bolt Rear End Gear Ratio Chart How to Install A Chevy and #135100610026 – Axle Ratio Chart, with 43 More files. 73 times to the wheels turning one, full rotation. The 35C version is found in the rear of Cherokees and Comanches. See the chart below the table for typical ratios. To use the Gear/MPH. Payload and Max Trailer Weights are ESTIMATED values. The truck achieved a best of 16. Right now same rear and trany (TH400) and stall behind a 360 280H cam it runs 13. 73 Ratio Rear Axle Assembly 107K Miles OEM (Fits. Enter in your info: Transmission rear gear tire height desired shift point It will show you RPM's in every gear at any speed. Differential Gear Ratio Calculators. Ratio may be determined by the number of teeth on the ring gear divided by the number of teeth on the pinion gear or by counting the ratio of the number of turns of the pinion relative to one turn of the axle shaft. 6 9 Fourth 1. Let's see, I have had 2. Axle Kits Axle Spindles Axles Chromoly Axles Differential Carrier Cases Differential Covers Differential Lockers & Spools Differential Rebuild Kits Driveshafts Gear & Install Kit Packages Housings, Dropouts & Pinion Supports Individual Bearings Limited Slip Differentials Miscellaneous Off-Road Recovery Gear Oils & Additives Ring & Pinion Gear Sets. Made from high quality 8620 forgings and Gleason gear cutting technology, these gears are made to last. The Extreme 60 high-pinion rear crate axle is the strongest 60 series axle that we offer, designed for severe off-road use with up to 40-inch tires and V8 conversion horsepower. above, the first letter in the code "G" denotes the ring gear diff size of the rear axle. If you need help choosing a gear ratio, Summit sales reps can help or you can use the Gear Ratio Calculator on Summit’s website to narrow down your choices. 0 L I6 3F petrol – FJ62 4. but again which rear end? PO Stoner, Mar. AXLE CODE CHART '94 TO 2004 yard's looking for 4. Dana design axles from 1977 thru 1980. EVER WONDER WHAT happens to your Gear Ratio when you put on a Larger or Smaller Right Rear or how many RPMs you gain or lose by changing a set. Gear Calculator Dealer Locator Dealer Login. 5" rim and 245 mm wide tires, they are rated at 630 revolutions per mile, so they need a slightly lower rear end ratio than a pickup truck would require, because the tires are taller. There is a plate or stamp on the rear diff that will tell you what the rear gear is. 73 open axle or 4. 8-inch axle along with bearing, collapsible spacer, and pinion. 55 to one, 3. 2)8 inch rear axlehow much wider will the '69 Mustang axle be than stock Maverick width? 3)I'll probably save the front spindles etc. Transmission's 5th gear ratio (or whatever the top is) Your typical highway cruising speed; The calculated rpm from above; and you run it through a gearing calculator to give you the optimum gear ratio you should be running with those tires. Whip out your calculator and follow along. Dana Differential ID Profile & Information. A 4x4 Differential Gear Ratio Chart Table. All of a sudden you find yourself and your T-car on that frightening creature called an Interstate Highway. 92 times for every one revolution of the axle/wheels. Low gears give fast acceleration, high gears give better cruising. I just typed in uneven numbers, and it worked. Enter the tire size diameter and the target vehicle speed in MPH. Dodge Ram 2009-Present: Gear Ratio Information. 73:1 all the way to 4. ) But here is a basic chart to help you decide: Although you should take the time to do the math and find out which ratio is best for your truck and tire combination, to make things easier we've put together the following chart. Yes, I understand how to come up with my overall ratios with the trans gear and rear gear, it's the chart that I can't figure out. The rearend gear ratio. above, the first letter in the code "G" denotes the ring gear diff size of the rear axle. New to dragracing been a dirtracer 40 years would like advice on gear for my s15 gmc. 08: 40/13: WE: YE: 1965: GTO: 3. It is really helpful to learn more about gear ratios and how to change out the rear end ones. 35] would provide decent off-the-line performance, even with a low horsepower engine. 42 were the most common. Installation of the correct ring and pinion gear ratio will help optimize performance, fuel economy and overall driveability. The taller tire grips 200% more then my shorter tires and 3. How to tell what gear ratio is in your CJ. The ratio of the speed of rotation of the powered gear of a gear train to that of the final or driven gear. Nitro Gear & Axle strives to provide the highest quality differential components available. Note: Gear tooth counts vary depending on the rear end axle ratio and the wheel/tire size. The change was intended to improve the truck's fuel economy. 50 rear end, it cruised effortlessly on the highway in OD and got 22 MPG. What Gear Ratio is My Rearend? You can find your gear ratio easily with this method. Gear Ratio and Tire Size Chart NEXT PAGE This gear ratio and tire diameter chart is meant to give you an approximation of ideal RPMs at highway speed (65 mph) for three situations: fuel economy, every day driving and increased towing power. If you're using a Schlumpf Drive plus an internal-gear rear hub you should enter the actual number of teeth of the front chainring for the first chainring, and this number of teeth times the Schlumpf ratio for the second chainring. speed as with the factory tire size, you would want to install a 4. This calculator is designed to give you a rear end gear ratio. Includes chart. 10 rear end gears. If that is the case you would have to pull the rear cover off, check the numbers on the ring gear and use the "Red" chart in post #2. March 18th, Chart of the different differentials on the w201 chassi. The 1962-63 serial numbers are located on the front, right side of the differential carrier. I'm the proud owner of Jeep YJ Wrangler, and I want to get rid of that crappy rear axle and swap it with the venerable 8. there are 4 lines that run opposite of each other. Differential Gear Ratio Calculator: Lift Changes with Rocker Arm Ratio Variations. Below are the stock gear codes found in the glove box. 8-inch differential is common across all of the ring-and-pinion ratios. I have used the search function and there are code interpretations that say my axle ratio is 4:10 but when I do the spin the one tire test - I count 45 and 2/3 rotations of the drive shaft per 20 times the wheel is spun. Calculate Rear End Gear Ratio needed To find the ideal gear ratio for cruising use your RPM at peak Torque. 73 and maybe a 2004R now too. Transmission's 5th gear ratio (or whatever the top is) Your typical highway cruising speed; The calculated rpm from above; and you run it through a gearing calculator to give you the optimum gear ratio you should be running with those tires. Just download and run it in Excel. 10 limited slip. See the Axle Ratio Calculator in the References section below for specific calculations. I race on a 3/8th mile track, have a stock 350 with a. For example, the default figures in the chart are for a stock ratio transmission as fitted to a Type 1, 1303S (3. At the other end, higher number such as 4. The Type O (Oldsmobile) 12-bolt rear ends use a smaller ring gear than the Type C (Chevy) 12-bolt, resulting in lower strength. It's actually kind of close to the 6sp and 4. and then the ratio of the bull gears to the bull pinions or whatever final drive your machine. Engine RPM, or the speed at which the engine turns, can be calculated at any speed given the vehicle's tire size, axle ratio, and final transmission gear ratio. The bottom diagram illustrates the differences in axle ratios. The first axle is used on 4cyl and some 6cyl cars and is a 6 3/4" ring gear integral carrier axle. and also when i put my truck in 4 wheel drive the front end clicks. I am thinking the short one goes on the driver's side as the ring gear is on that side. A good way to calculate this is to multiply. Unlike a locker its very streetable. Prior to the 10 bolt/12 bolt rear axles that came out in 1965, the axle housing was the same for all ratios. 66 Second 2. gear ratio such as 53 x 12T is. 2)8 inch rear axlehow much wider will the '69 Mustang axle be than stock Maverick width? 3)I'll probably save the front spindles etc. 55 gears work with no more modifications ? daddio Dodge Dakota JOIN HERE 7/12/2011 13:39:40: RE: Gear Ratio??? IP: Logged Message:. GMC / CHEVY REAR AXLES. Click “Calculate Gear Ratio”. In this video I break down in great detail the speed at which your car will be going for every 500 engine RPM with each typical rear gear ratio for each gear of the transmission and then reverse. In the context of the final drive ratio (rear end), it's the number of turns the driveshaft makes per turn of the axle. Step 1: Place the oil catch pan under the rear differential cover. Enter the maximum potential safe engine RPM. Probably the pre-eminent expert in this area is Carl Cederstrand of the Vintage MG Club of Southern California (VMG). The rear axle gear ratio is the number of turns that the input of the differential at the driveshaft makes in relation to its output at the rear wheels. Second Strike Gearing Calculator. i dont have my build sheet in front of me, but on my r/t i have the 3. 10 gear ratio. Engine RPM divided by total gear ratio, multiplied by the tire diameter and converted for units of measurement, gives vehicle's speed of travel. Ford used them from 64 to 73 in their cars. This chart applies to all Ford non-overdirve transmissions, manual and automatic. March 18th, Chart of the different differentials on the w201 chassi. It only shows cars that were available in the US. What Gear Ratio is My Rearend? You can find your gear ratio easily with this method. 10:1, and so on. Unless driven gears with more than 45 teeth and / or drive gears with fewer than 15 teeth become available, it will be impossible without using a ratio adapter to have an accurate speedometer with rear end gear ratios lower (higher numerically) than 4. on the door plate; so far this turns out to be a 3. Tweets by @@HotrodPitstop. Gear ratio, or in a car, final drive ratio is basically the number of times the tires rotate in relation to the number of times the drive shaft or axles rotate. We have the largest selection of General Motors S10/S15/Sonoma Rear Axle Assembly parts at discount prices. Last, I have seen MANY 55 rearend cases that DO NOT have a casting date or a stamped code. It was possible to change gear sets simply by swapping the pumpkin. If it was stamped BB, the first B would be for the Buffalo plant. Search Results for Rockwell Rears (Rear) on HeavyTruckParts. 42 gear ratio you're limited to a trailer in the neighborhood of 9,000 lbs (truck weighs 8,000 lbs, GCWR with 3. i got my info from the jan 03 issue of four wheeler mag. No stickers anywhere, not in glove box, not in door frames, not on axle, not in manual. Drag Performance Calculator By AssassinRacing. My Porsche runs like a scalded ape in first gear and it's overall ratio is 13. You can use it to quickly estimate your trucks best gear ratio. ), and of course the ring and pinion gear set. Extreme 60 Features: High-Pinion Design With Ring Gear Load Bolt; High-Clearance Radius Bottom Center Section; Low-Friction Hardened Steel Skid Plate. Read More. Positive identification of the Corporation (Chevrolet) axle versus the Dana axle is necessary for proper selection and ordering of service replacement parts. Quick Change Gears. Two styles were used. It is located on the right hand side of the case and is composed of two letters. The Type O (Oldsmobile) 12-bolt rear ends use a smaller ring gear than the Type C (Chevy) 12-bolt, resulting in lower strength. Two things to know, the final drive ratio and type. Enter the maximum potential safe engine RPM. To do another, enter a new set of values. All of a sudden you find yourself and your T-car on that frightening creature called an Interstate Highway. The number of rear axles will usually determine what axle truck it is. Axle Ratio GVWR Payload Base Weight GAWR GCWR Max. J/S In Sprockets 24 tooth are primarily for Karts. Let’s take a hypothetical engine with 500 ft. 52 first gear times the rear end ratio of 3. 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. They had a ring gear diameter of 7 and 9/16 inches. I am looking to get a 2019 Ford F350 dually. Inside the differential cover, the ring gear will be marked with tooth counts such as 10,41 for 4. You need to know the teeth counts of each gear set that is involved with the power flow of the tractor and find ratios of them individually. In my experience over the years, on 11R22. I tend to start in second often. Here is a cgi I wrote to do gear ratio calculations. the 4:10's stay in 6th gear most of the time except on very steep grades. On 4x4’s, there is a Dana 28 axle up front, until late 1989 when it was replaced with a special Dana 35. With this calculator, you can solve for any of three variables in the rpm-speed equation. The five speed option is for the last gear of a transmission greater than four speeds. 1978 Corvette Specifications - 1978 Corvette Spec Sheet. 12 by your tire diameter. Toyota has provided 4 differential types in pickups and 4Runners -- the 8" standard, the 7. Jump to Latest Follow 1 - 20 of 423 Posts Mine says GQ1 I have been to a few places and nobody seems to know my gear ratio, So I guess I'm an. It was possible to change gear sets simply by swapping the pumpkin. Created to fill a space between the imported, compact Dodge Ram 50 (an un-altered Mitsubishi pickup) and the Dodge Ram, the Dakota came with two Chrysler-built engines, a 2. 25-inch oval. 92 gear ratio rear axle. the ratio of each gear speed in the transmission, 3. Transmission Gear Ratio Equation and Calculator Mechanics and Machines Calculations Menu The following equations and calculators will estimate the resultant vehicle speed at a known engine rpm for a manual transmission with up to six forward gears. 08: 40/13: XE: ZE: 1965. Rockwell Differential Axle Codes · Rockwell Differential ID Chart & Profiles · Differential ID Locations, manuals and parts. Axle Ratios Transmission Codes Production Totals Price $ VIN Decoder · 1973 Body Styles Grille Styles Rear Styles Wheel Styles Special Models Sales Brochures Measurements Paint Color Codes Engine Data Axle Ratios Transmission Codes Production Totals Price $ VIN Decoder · 1974 Body Styles Grille Styles Rear Styles Special Models Sales Brochures. Ford has changed the tag over the years, but generally the appliction number-which begins with the W on line one, the gear ratio and date code are always given. It is based on the above formula. Alright guys, i have a 1966 200ci mustang with a t5 (2. rear axles and ratios. 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. In this case, the gear ratio is 4. 42 is 17,000 lbs). I originally went with 3. 92 gears, no towing package, but i also have the corporate axle, but i cant remember if it is 8. Mustang Rear Gear Ratios Overview. Also see AMC Automatic Transmissions Chart. In my experience over the years, on 11R22. 72) in my IH scout with a 6 cyl. i dont have my build sheet in front of me, but on my r/t i have the 3. Calculate your Rear End Gear Ratio Needed. This is what I found on the ring gear. If your vehicle has a low gear ratio, you can offset this by installing slightly larger diameter tires. The 10-bolt differential cover is located on the rear of the axle and is an 11-inch x 10. 8-inch Ford rear end, as an alternative to using the 9-inch Ford third member or a GM posi differential, can save the enthusiast some hard-earned cash, and its adaptability as a conventional open differential or a limited-slip unit can offer you a wide range of performance possibilities. 6 to cooperate with my rear end gear and tire size, long story. com Calculate the theoretical 1/8 Mile ET, 1/4 Mile ET, 1/4 Mile Top End Speed, and Ideal 1/4 Mile Gear Ratio for a given application based on the Vehicle Weight (in pounds), Vehicle Horsepower (at the flywheel), RPM through lights (finish line), and Tire Diameter (Height) in Inches. Just like a 10-bolt rearend, there should be stamped numbers on the axle tube - on the passenger's side. The main reason for checking these tags is to see the axle’s gear ratio. Exclusive 9 Gear Ratios. Bigger tires can help you crawl up those slick rocks, look cool, and rob you of power. It is and should be the product of all gears in use, from flywheel to tire. The Bill of Materials (B. A commonly overlooked component of a vehicle's drivetrain that has a large effect on fuel economy is rear end gearing. Speedometer gears in the transmission are made to match the rear differential gear ratio. A truck without a high enough rear axle ratio might perform well at highway speeds, but might be slow to start while hauling a heavy load. Quick Change Gear Chart; Quick Change Gear Chart : Product Description. Also calculated is the new gearing you would need in order to return back to your original gear ratio when going to a bigger or smaller tire. We prefer to call this the drive ratio. The engine is connected to the gearbox, the gearbox, via the tail shaft to the differential, and the differential via the axles to the wheels. 0 L I6 3F petrol – FJ62 4. if you know anything about it, email me at [email protected] thanks. RPM Calculator Input - Note: Currently using 94-95 T5 specs and 3. Right now same rear and trany (TH400) and stall behind a 360 280H cam it runs 13. : this calculator allows you to enter 3 of four variables and it will compute the other based on your input. 73/1 code GT4. 70 for the automatic and 0. If our input gear (10 teeth) is rotating at 5 rpms , and it is connected to our output gear (50 teeth), our output gear will rotate at 1 rpms. Towing a 16,000+ Lbs 5th Wheel Camper with Ram HD 3500 Dually turbo diesel: Does the Rear Axle Ratio Matter? (Ask TFLtruck). Buyer is responsible for verifying compatibility with their vehicle. 55) is going to be a lower ratio and give you better acceleration. 25 gears and I inquired about faster ratios for it and was told that was the highest ratio offered. Because different transmission gear ratios can greatly affect a drivetrain combination, it's important for anyone performing a transmission swap to know the gear ratios of the gearboxes you might be installing in your vehicle. NOS 1940 1952 Chevy Rear End RING GEAR & PINION 37:9 Original 1953 SDN DELIVERY Chevy Truck 14 Bolt 4. 58 already with much success. 5 MPG using 3 rd gear. 12 by your tire diameter. 30 gears in their axle is because the transmission ratios are insanely tall. The Dana 44 ring gear size is 8 ½ inches. This calculator assumes you know the vehicle's transmission ratio. Is there a formula or a chart to tell what size gear is in the rear end of an 8 3/4 without pulling out the pig and reading what's stamped on it? it has been so long since I did something like this I just can't remember how it's done. The S13 held up great but my biggest issue is the rear end gearing. If you have ever wondered what the gear ratio is in your rear-wheel drive vehicle and. Well I found part of the differential's ID tag on the ground a while back and this is what was written on it. A rear gear training. You can change one thing at a time, such as cruising speed, and determine what gear you like. 103:1 (which rounds off to the readily available 4. these rear ends can be found on all 4-speed manual 4-cylinder trucks. Since the gear tooth pitch is slightly different than OE, the service life of this gear is limited to less than 25,000 miles. The truck achieved a best of 16. You will have one and possibly two of the following codes if you have the G80 option. Listed are the expected RPM's at 60 MPH with a given rear end ratio and tire height. On OEM gear sets, the ratio is usually stamped on the ring gear edge. 55) is going to be a lower ratio and give you better acceleration. GEAR RATIOS FOR SPROCKETS Lowering the ratio increases top end speed - Increasing the ratio increases acceleration and bottom end power. 64 first gears, and with smaller cubic inch engines first gear. The value will be returned in estimated differential gear ratio, based on the entered values…. When I called a Ford service dept, they told me they could only check back to 2000, but the H9 indicated a 3. Full sized poster versions of of the charts shown below are available for purchase. The left side of the calculator requires all three entries. Gear ratio, or in a car, final drive ratio is basically the number of times the tires rotate in relation to the number of times the drive shaft or axles rotate. Easy to use parts catalog. I have an A833 tranny which gives me a 0. 05 tire rotations for 2 engine rotations, which figures out to a rear end ratio of 3. 70 overdrive which is multiplied times the rear end ratio for the finial drive ratio in OD. You know the tire height in inches. It is located on the right hand side of the case and is composed of two letters. Need Meritor/Rockwell Gear Set Parts? Check out 171 Meritor/Rockwell Gear Set Parts for sale. Yesterday I pulled the center section on the rear end from my 1955 Fairlane Club Sedan to check ratio and condition. 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. Re: Dana axle identification I have a built up rear dana 44 in my yj and while doing a disc brake conversion I find that one axle shaft is a little longer than the other. I am thinking the short one goes on the driver's side as the ring gear is on that side. I have exhausted the search function and now I would like to know what my Toy has. Maybe slightly less. 65 for the Speed Drive, and 2. If that is not there, there are other ways of figuring it out, just search forum and you will find numerous threads on it. 10 when I first started my rear end build. Use our Differential Gear Ratio Calculator page to determine the best ring and pinion gear ratio for your vehicle. You can also now calculate when using different transmission gear ratios, like in first gear or in overdrive. Installation of the correct ring and pinion gear ratio will help optimize performance, fuel economy and overall driveability. 36 R200 Final Drive $595. The gear cluster (input shaft and output shaft) is mounted in a removable cassette, which can be removed once the gearbox/rear suspension/wing assembly has been removed from the rear of the car. About Us Introduction Why MFactory? Contact Us. Gear Ratio and Tire Size Chart NEXT PAGE This gear ratio and tire diameter chart is meant to give you an approximation of ideal RPMs at highway speed (65 mph) for three situations: fuel economy, every day driving and increased towing power. @ Easy To Follow Pulley Ratio Rpm Calculator For Rear End Gear For Beginners And Advanced From Experts | Easy To Follow Free Download PDF Wood Building Design. those are the only full floaters that gm used. 91 gear ratio, at least for the 5sp. These RPO codes are used to idicate a specific type of differential and/or ring gear size. Tire Size 2. On 4x4’s, there is a Dana 28 axle up front, until late 1989 when it was replaced with a special Dana 35. The following table shows the various Ford part numbers and gear ratios for the matched ring and pinion gear sets used on 1928 through 1934 Model A (103-1/2" WB) and Model B (106" WB) Ford car and commercial chassis, not trucks. 78 in my Old's to a 3. The following conglomeration of information should help a person be able to locate, identify, and install an 8 3/4” Chrysler rear axle in their AMC product. 0-liter Ford Rangers and Explorers/Mazda Navajos. AXLE RATIO & IDENTIFICATION Ratio is determined by dividing number of ring gear teeth by number of drive pinion teeth. No stickers anywhere, not in glove box, not in door frames, not on axle, not in manual. Pulling the cover is the guaranteed way to find out what you have. Need help with rear end identification for your. If you do not know this ratio, you can simply put in 1. See my chart below. It is a banjo-type ( Hotchkiss ) axle, ie. We stock thousands of truck differentials as well as new and used rear ends, axle repair parts and supplies. NOTE: See chart. The whole rear axle is set up with QP parts, very happy with the end result. ) Tire Height - In Inches, Use The Gear Calculator or Tire Size Calculator Speedo Revs/Mile - Number of RPM the speedometer needs to turn at 60mph You can hit the SAMPLE button to see how some typical calculations will look. Easy to use parts catalog. However, determining the rear differential ratio is fairly easy. If the driveshaft rotates about 3x, the gear ratio is 3. This banjo rear end conversion requires the use of 1939-1948 Ford or 1939-1941 Lincoln hydraulic backing plates and a 1940 Ford-style drum. Techno’s “Know your car” Series # 8 Mazda MX-5 Gear and Differentials Ratios and Tyre Sizes Introduction. A huge thank you to 1 Wild R/T for suggesting it. 25 (i think it is 8. gear ratio such as 53 x 12T is. The engine is connected to the gearbox, the gearbox, via the tail shaft to the differential, and the differential via the axles to the wheels. Buyer is responsible for verifying compatibility with their vehicle. 10 rear end gears. 1) Jack up one rear wheel and chalk-mark the 12 o'clock position on the tire. RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Majority of semi-trucks are equipped with one front steer axle and two rear axles combined as a tandem axle. Gears, axles, locker, limited slip, kits, driveshafts, transfer cases and more. The HEMI is more than capable of making this truck perform no matter the rear end. If you don't know what the rear end ratio is in your truck it can be calculated from other info that you may know. To determine which speedometer gears are needed, you need to know two things, tire diameter and rear end gear ratio. Note: All 1970-1982 Corvette rear axles were Positraction. (I love it). See the Axle Ratio Calculator in the References section below for specific calculations. com 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. Richmond Gear is the leading manufacturer of professional quality, high performance ring and pinion sets. Dana axle identification is located on axle tube between Steering Shock Absorber Bracket and the Carrier. Divide the ring gear teeth number by the number of teeth on the pinion. Hopefully, it is easy to interpret. The Detroit Truetrac is a helical-gear style, limited-slip differential that maximizes wheel traction and enhances driving characteristics. I'd keep the 3. This calculator is a useful tool that will do the math to help you figure out the gears that are needed to make your speedometer work correctly. My charts are not the gospel on gear ratio's, but will give you a decent idea. 67-81 REAR AXLE. Using the charts below, you will be able to learn alot about the rear differential in your classic full size Chevy. 90 which is hardly worth the effort if you already have a 4. 55:1 gear ratio you find in most automatic XJ Cherokee’s is perfect for the stock tire size or even a little bit larger. Gear ratio, or in a car, final drive ratio is basically the number of times the tires rotate in relation to the number of times the drive shaft or axles rotate. Enter the tire size diameter and the target vehicle speed in MPH. If you do not know this ratio, you can simply put in 1. This axle features a drop-out style carrier with a 8-3/4" ring gear, 30 spline axle shaft, and was available in three different case styles with different pinion shaft diameters. Your entire Mustang's rear consists of your axles, the gear housing, a power transfer device (IE a spool, LSD, posi-unit, etc. A good running bone stock 460 should murder the rear tires simply by hitting the loud pedal good and hard regardless of axle ratio. Ford used them from 64 to 73 in their cars. People who are buying a used vehicle, or shopping for an axle from a junk yard, frequently need to know what the ring and pinion gear ratio is in the axle's differential, as well as whether or not the axle has some sort of traction control device like a limited slip, locker, or spool. Tags are generally found attached to the passenger side of carrier. So again, unlike the GM and Dana axles that require a unique differential with different ratios, the Ford 8. If you don't know what the rear end ratio is in your truck it can be calculated from other info that you may know. 454 AXLE RATIOS & IDENTIFICATION 0 1997 ADP Claims Solutions Group, Inc. 38 gears, which is the optional 4-cylinder gear ratio. 66 Second 2.