Lift one of the back wheels. Switch to neutral and let go of the parking brake. Mark the driveshaft to the differential and the wheel in the air to the backing plate with a piece of chalk as precisely as you can. When the wheel has completed exactly one round, turn the shaft and count the revolutions (and portions of them). 3.73 will be 3 and just under 3/4 shaft turns. 4.1 turns just over 4, 4.3 turns just over 4, etc.
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What makes my Toyota differential unique?
I need some assistance identifying the most prevalent codes! I will update the table below after you send me an email with your truck’s C/TR/A/TM code, engine type, transmission type, model year, stock tire size, and country of purchase. I’m attempting to determine precisely which gearsets were available with each engine/transmission combo. I’d like to make this table as complete as possible and would like to know if there are any other inexpensive switch options, so if you have other Toyota vehicles, please give me those codes as well.
While 4.10 axle gearing is typically included in toys sold in the US, it isn’t always the case. 4.30 gearing is frequently found in four-cylinder autotransmission vehicles (4.87 if they came factory-equipped with 31″ tires). 4.56 gears were typically standard on all V6s with 31″ tires and 4-cylinder manuals with 31″ tires. And still more have had their owners modify them so they can move bigger tires.
Look for an information plate on your truck, either on the firewall (if it was manufactured before 1989) or the door jamb, to help you identify your axle type and standard gearing (1989-current). The appearance will be similar to this:
The Color (paint) code, Trim Code, Axle Code, and Transmission Code are represented by these numerals. You should also double-check your VIN number’s initial few digits.
A letter that designates the ring gear’s diameter appears in the first place of the axle code. The 7.5″ and 8″ diameters have always been utilized in Toyota vehicles and 4Runners, however the other diameters are listed here for completeness. For Toyotas made in Japan, the first table is applicable; these vehicles’ VIN numbers start with “JT”. Vehicles with a VIN starting with “4T” in North America are covered by the second, smaller table.
For instance, the code for my Japanese truck is G282. This indicates that I have a 2-pinion design, an automatic transmission, and an 8-inch (rear) axle with 4.30 gears (common in 4 cylinders).
The numbers in the first table’s highlighted cells are those that you’ll most frequently see in Toyota 4Runners and pickup trucks.
I need some assistance identifying the most prevalent codes! Please email me with your C/TR/A/TM code, engine type, transmission type, model year, stock tire size, and country of purchase of your truck so I can update the table if your truck or 4Runner (heck, even your car) includes code parts that are NOT mentioned above.
This second table contains a number of discrepancies that we’ve discovered, so don’t accept it as gospel. As of yet, the first table has shown to be reliable.
What is the gear ratio on my Tacoma?
By reusing key components across many models, Toyota is able to produce cars with such a solid reputation for dependability. In addition to generating the volume that lowers the cost of those components for you, the end user, doing so also secures a nearly universal supply of those components.
If you need to special order an engine part for a more exotic vehicle, you could have to wait weeks for it to arrive. If you need a Tacoma engine part, practically every vendor in the US will have it in stock. This is due to the fact that the Camry, Highlander, Sienna, and no fewer than five other models from Toyota’s luxury division, Lexus, all share the Taco’s 3.5-liter Atkinson-cycle V-6 engine. In ten years, it will be exponentially simpler and less expensive to maintain a Tacoma thanks to the parts’ commonality.
Toyota has opted to equip the truck with rather tall gear ratios in order to produce a truck that can provide impressive fuel-economy results in the Environmental Protection Agency’s standardized test cycle (up to 19 miles per gallon in the city and 24 miles per gallon on the interstate). The V-6 is rotating at 1,500 revolutions per minute at 60 mph while in sixth gear. Although there are significant trade-offs in terms of practical drivability, this is perfect for yielding good fuel economy in the EPA’s highway-test cycle, where the top speed is 60 mph.
That 3.5-liter V-6 in the Tacoma produces a respectable 278 horsepower and 265 pound-feet of torque, but only at high engine speeds. The engine produces somewhere between 50 and 100 pound-feet of torque and horsepower at 60 mph in top gear, where maximum horsepower is reached at 5,374 rpm and maximum torque at 3,037 rpm.
To give you the performance you demand, the transmission will need to downshift by two or three gears if you put your foot down at that speed to pass another car or climb a hill. This holds true whether you’re shifting with a manual or automatic gearbox. The Tacoma’s extremely high gear ratios are ideal for official fuel-economy ratings, but in practice, drivers will discover that the transmission downshifts far more frequently than necessary, making it impossible to meet those figures. You can anticipate Tacomas to have an average fuel efficiency of around 18 mpg if you look at the 2,287 third-gen Taco owners who submit their own statistics on Fuelly.
But instead of using the fast lane, what Tacoma owners typically do wrong is install bigger tires without making the appropriate adjustments to sustain them.
Off-road, greater obstacles are easier to roll over with larger tires. And they look cool. Therefore, adding bigger tires is likely the most frequent alteration performed to a truck. But bigger tires also result in a lower effective gear ratio for a vehicle. This poses significant difficulties given how tall the Tacoma’s gearing is. You can increase your Tacoma’s stock 30.5-inch tires to 34 inches and spin those 1,500 rpm at 70 mph. That might not offer enough power to sustain top gear while driving steadily at a constant speed on a flat road, forcing the usage of lower gears everywhere and putting more strain on the engine at every speed. In other words, it ruins fuel efficiency and creates an unpleasant driving situation.
Stuart says that after installing 34-inch tires on his Tacoma without regearing, he was averaging about 12 mpg on the interstate. Even a 10% increase in tire size reduced fuel economy by half compared to the claimed number.
“I remember flooring it up a grade in the summer of 2019 while traveling from Southern California to Montana via Colorado, just making it to 60 miles per hour, he says. ” At 7,000 feet, the engine was working extremely hard to maintain highway speeds. Semis were moving ahead of me in speed. Back on level ground, the speed was so sluggish that passing in the oncoming lane was actually dangerous.
Off-road, where performance rather than fuel economy is the main focus, is where the issue is much worse. Your car’s horsepower and torque will go farther down the road if its effective ratio is decreased. By shifting into distinct, extremely low gears, off-road vehicles may safely ascend and descend steep obstacles at very low speeds. These gears increase the force the engine can apply to the wheels by a quantity given as a straightforward ratio.
A standard Toyota Tacoma TRD Pro has a crawl ratio of 36:1 for automatic transmissions and 44:1 for manual transmissions. You can see that the Tacoma’s gearing is already subpar on highly steep obstacles when you compare those gear ratios to an off-road vehicle that is more specifically designed, such as the Jeep Wrangler Rubicon (with an 84:1 ratio). Increased tire size will further reduce that. As a result, it’s typical to witness films of Tacoma drivers ascending slopes at excessive speeds, risking damage to their cars in exchange for the forward momentum required to complete the ascent.
In order to complete a climb, a Tacoma driver is required to use momentum rather than changing gears, as seen in this Fast Lane video. This kind of driving will eventually harm a vehicle, and attempting tricky off-road barriers at high speed also increases the likelihood of a rollover or other mishaps.
What can you do in this regard? Fortunately, there is a really good solution: you can raise your final drive ratio by changing the gears in your axle differentials. You have the option of increasing the final drive ratio or bringing it back to a level that is similar to stock after accounting for the effective gearing decrease generated by the larger tires. Installing gears that raise the Taco’s V-6 engine speeds at 60 mph to roughly 2,000 rpm will maximize performance and fuel efficiency, allow you to sustain highway speeds without downshifting, keep the engine running in its most efficient rpm range, and improve safety and off-road control.
The 3.91:1 final drive ratio on the Tacoma may be changed to either 4.88 or 5.29:1 by Nitro Gear and Axle. In addition to being able to pass 18-wheelers on two-lane roads, Stuart would have averaged closer to the 18 mpg statistic that most owners of stock Tacomas record if he had installed 5.29 gears at the same time he added the 34-inch tires. Budget roughly $3,000 for regearing if you intend to place bigger tires on your Tacoma (which should cover both parts and labor).
Here’s a new, entertaining hobby that any of us can undertake at home. Find a Tacoma on Instagram, then make some calculations on a piece of paper. Let’s make some conservative estimates for this one, going backwards from the front. 100 pounds for the front bumper. Sliders for rocks: 100 pounds. 40 pounds for the roof rack. 50 pounds on the bed rack. 150 pounds of unsightly canvas was piled up. Maxtrax knockoff: 15 pounds. 30 pounds for high lift. 90 pounds of extra fuel equals fifteen gallons (there are two Rotopax on the other side). 120 pounds for the rear bumper with swing-out. 50 pound large spare tire This Taco weights at least 5,190 pounds before taking into consideration the weight of a driver and passenger, a full tank of fuel, and anything they are hauling inside the cab or bed.
What does my vehicle’s VIN tell me about it?
A VIN is a string of 17 characters, including capital letters and figures, that serve as the vehicle’s individual identification number. The manufacturer, special characteristics, and specs of the vehicle are shown on the VIN. Tracking recalls, registrations, warranty claims, thefts, and insurance coverage are all possible using the VIN.
What is the Toyota Tundra’s gear ratio?
Thanks to the optional heavy-duty TripleTeach frame with an integrated tow hitch receiver, the 2021 Tundra can tow up to 10,200 lbs. The Integrated Trailer Brake Controller, which helps you regulate the amount of trailer braking based on weight, is another towing function that is offered. A tow hitch receiver, a heavy-duty battery, Trailer-Sway Control, a 4-/7-pin connector, and other items are all considered standard towing equipment. The maximum payload for the 2021 Tundra, when properly outfitted, is 1,730 lbs.
Powertrain and Performance
The 5.7L (346 cu) i-FORCE V8 and 6-speed automated transmission are standard on the 2021 Tundra. The engine generates 401 lb-ft of torque and 381 horsepower. With a 4.30 rear axle gear ratio, the 2021 Tundra is able to produce a lot of low-end torque. Both 2WD and 4WD versions of the 2021 Tundra are available. There is an automated limited-slip differential on every 2021 Tundra model. Due to the A-TRAC system and the 2-speed transfer case, the 4WD variants of the 2021 Tundra also have active traction control.
What 10 bolt rear end do I have, and how do I know?
The 12-bolt Chevrolet rearend seems to receive all the praise when it comes to Chevrolet rearends. Rightfully so, as it is undeniably the more durable of the two when compared to the 10- and 12-bolt units. When employed in high-performance, high-horsepower applications, that is typically demonstrated. However, the 10-bolt rearend is essentially a fantastic component for a street/strip car and can be robust enough to withstand even the occasional abuse caused by use at the racetrack.
Two small cast-in protrusions are located close to two of the bottom cover bolts on the housing of the 7.5 rearend, which has an oval cover. This 7.5 rearend can be used for any 197888 GM A or Gbody intermediate, such as a Cutlass, Monte Carlo, El Camino, Malibu, Regal, or Grand Prix. It is indicated by the control armmounting ears on top of the rearend.
searching for a 12-bolt that is “cheap, is becoming almost impossible to achieve. Because of this, a lot of enthusiasts are thinking about the 10-bolt. But did you realize there are various 10-bolt rearend designs? One measures 7.5 inches, another 8.2 inches, and two more measure 8.5 and 8.6 inches. You must be able to precisely identify the various components if you’re seeking for a solid, affordable 10-bolt rearend to repair or install into your hot rod. Otherwise, you risk unintentionally purchasing a 7.5 or 8.2-inch differential.
If you find a rear end with coil spring perches, it might come from an El Camino, G, A, or B-body.
Over a long period of time, both vehicles and trucks used the 8.5-inch 10-bolt rearend. As a corporate replacement for the 8.2-inch 10-bolt rearend, it initially appeared in production cars in 1970. With the exception of Cadillac, all GM divisions used it in various versions. Since they were so commonly utilized, your chances of finding one in a salvage yard are higher than those of finding a 12-bolt. That was the driving force behind our decision to create this swap meet/junkyard identification guide. You won’t unknowingly spend money on something you don’t actually want if you do it that way.
There are literally hundreds of possible codes for the three separate 10-bolt rearend housings, but the code stamps, which are often on the passenger-side axle tube, can be used to determine the 10-bolt rearend’s provenance. Since it would be difficult to name them all in this post, we’ll simply be concentrating on visual identification.
Although the 7.5-inch 10-bolt and 8.5-inch housing are very similar, measuring it will allow you to absolutely identify the Chevy 7.5-inch rearend. The cover’s oval shape has dimensions of 8 5/16 by 10 9/16 inches. The cover’s bottom center bolt and its surrounding bolts are spaced apart by 3 1/4 inches. The ring-gear bolts on the inside are identical to those on the 8.5 corporate unit, but the pinion-shaft diameter is 1.438 inches instead. The axles are secured in place by C-clips on the inner end of the axles, just like the majority of 10-bolts.
This table translates the code from the axle tube’s stamped date and manufacturing location.
A 10-bolt rearend is frequently a 7.5-inch unit if you find one. Up until the 2005 model year, these have been used under cars, small trucks, and vans since 1975. The 7.5-inch rearend should hold up behind an engine with 350 hp if employed in a daily car or cruiser application, even if traction is limited during aggressive driving. If sticky tires are utilized, the 7.5-inch rear will swiftly degrade into a mess of broken pieces.
This axle measures 8.2 BOP. BOP is an acronym for Buick, Oldsmobile, and Pontiac. Although it differs inside from the 8.2 Chevy, it uses the same bosses and brackets on the outside. The gears will not, however, work with a Chevy 8.2. At the outer bearing, four-bolt retainer plates rather than C-clips are used to hold the axle shafts in place.
Numerous 8.2-inch axle assemblies were produced, and although being just somewhat more powerful than the 7.5-inch rearend, they do have some aftermarket support. However, it is not advised to be used in conjunction with engines that have a significant level of horsepower. Again, in a daily driving or cruiser use, this might be acceptable, but if fitted behind an engine with horsepower figures that soar into the 400 range, you can anticipate a failure eventually. While a carrier-bearing girdle for the 8.2-inch rearend is available and does provide some support for the housing, it is not a dependable or sufficiently robust option.
The housing’s form and the distance between the bottom bolts on the cover make it simple to recognize an 8.2-inch rearend at a glance. The 11.2-inch cover has a diagonal protrusion at the top, while the 8.2-inch 10-bolt has a smooth, round, lower-case region (no cast-in protrusions). Additionally, a 10 5/8-inch cover with an odd shape is used. If the OEM pinion nut is still being used, the pinion nut should also be 1 1/8 inches in diameter.
The ring-gear bolts within the 8.2-inch 10-bolt have 9/16-inch socket heads and 3/8-24 left-hand threads. There are 25 splines on the 1.438-inch-diameter pinion. The axles are held in place by C-clips on the inner end of the axle shaft inside the carrier, just like all Chevy 10-bolts.
This kind of huge spring perch is used in the rearend of either an X-Body or an F-Body vehicles.
Strong and efficient differentials that can take more power than either the 7.5-inch or 8.2-inch rears are the 8.5-inch and 8.6-inch 10-bolt rears. The 8.6-inch (8.625) rearend was used on trucks made in 2000 and beyond, while the 8.5-inch rearend was used on cars up to 1999. Looking at the brakes is the simplest approach to identify the differences. Drum brakes are found on all 8.6-inch rears, while disc brakes are found on 8.5-inch ones.
There are two variations of the X and F-body spring perches: the mono-leaf (left), which is shallower than the multi-leaf (right).
Due of the ease of interchangeability of aftermarket carriers and gears, the 8.5-inch 10-bolt rearend is extremely popular. Gear ratios used to range from 2.41 to 4.10. You must be aware that there are various differential series (series two and three). The differentials will handle all gear ratios without switching carriers, with the exception of truck differentials with 30-spline axles and those carrying 2.41 and 2.73 gears (series 2). The 12-bolt, which costs more, has a pinion shaft that is the same diameter as the 8.5-inch 10-bolt.
An 8.5 will have two squared-off casting pieces dangling on either side at the bottom of the differential when viewed from the rear of the housing. The outline of an 8.2 (shown) will be the same as the cover. The odd protrusion at the top is also present on the majority of factory 8.2 covers.
The differential housing’s bottom has two extruded, cast-in lugs at the 5:00 and 7:00 locations on the majority of 8.5-inch 10-bolt rearends. The 8.5-inch rearend covers are frequently 11 inches in diameter and have a bulge on the driver’s side to make room for the ring gear. The cover’s lower center bolt and either neighboring bolt are spaced apart by 3 3/4 inches. The OEM pinion nut has a 1 1/4 inch diameter.
The ring gear is secured to the carrier by ten 3/4-inch hex head bolts with 7/16-20-inch left-hand threads on the 8.5-inch 10-bolt rearends. The pinion shaft has either 28 or 30 splines and measures 1.625 inches in diameter. The 8.5-inch 10-bolts, like the 8.2-inch 10-bolt, hold the axles in place with C-clips.
A portion of the 8.5 rearend’s round cover will extend rearward to create place for the ring gear. The massive, flat, cast-in protrusions at the five and seven o’clock positions will also catch your eye. Compared to the 7.5 rearend, these protrusions are greater.
There is a problem with the “corporate 8.5-inch axle assembly that was used in a small number of 1969 through 1972 Pontiac automobiles, some 1971 and 1972 Buick and Oldsmobile models, as well as the 1970 through 1972 Monte Carlo. Similar to an 8.2 BOP rearend, these axle assemblies use bolt-in axles to secure the axle in the housing rather than a C-clip. But it’s hard to find one of these because performance fans love them so much.
Pull the cover off and examine the bolt holding the spider gear crosspin to determine whether the rearend is an 8.2 or an 8.5. It is an 8.2 if it requires a 1/2-inch wrench to remove it. It is an 8.5 if it requires a 5/16-inch wrench to remove it.
For the 10-bolt rearend, many differentials are available. Nevertheless, there are just a few gear sets available for the carriers, especially if you want to alter the gear ratios. 10-bolt differentials are frequently tailored to a particular set of gears. With 2.56 and higher gears (numerically lower), such as 2.41, a Series 2 carrier will function. These are regarded as highway gears that are suitable for top speed rather than quick acceleration. Gears like 3.08 and 3.73 function well with the Series 3 carriers since they are best used with 2.73 and lower gears (which are numerically higher).
Unfortunately, it is virtually impossible to distinguish between the two units until you have them side by side. If you turn both units on their sides and measure the distance from that surface to the face where the ring gear attaches, you will be able to see the difference.