In order to understand how to use the differential lock in certain driving situations, it is necessary to understand the structure and operation of the car's transmission elements.
The Toyota Prado 90 used a permanent all-wheel drive system with the installation of 3 differentials (2 interwheel and one interaxle).
A differential is a mechanical device that divides the input shaft torque between the output shafts.
What does permanent four-wheel drive mean?
In simple words, the torque from the engine is transmitted through the gearbox and transfer case to all the wheels of the car, being distributed in almost any ratio, depending on their adhesion to the road surface.
At the same time, an open differential can transmit rotation, including in a ratio of 100%: 0% - when one of the drive wheels takes on all the torque,
usually this happens when one of the wheels is hung out.
If you raise one of the wheels with a jack from the ground, the car with permanent all-wheel drive will not budge.
The use of such a system on cars greatly unloads the transmission elements, thereby extending its service life. But what if the car is designed to move not only on good roads, but also off-road? Just for this, it is possible to block the differential, thereby distributing equally the torque to the output shafts.
Center differential lock
If you turn on the interaxle lock, the torque is distributed between the front and rear axles 50 × 50. In other words, when using this lock, the front and rear axles are simultaneously activated, while the torque is distributed to the wheels by interwheel differentials. A typical situation when the car stops moving when the center differential lock is on is diagonal hanging of the car, in this case the wheel lock helps.
The center differential lock can be engaged on the move at speeds up to 100 km/h. The orange indicator on the instrument panel lights up. It is used for driving on bad roads, with ice, for a more stable behavior of the car.
Cross-axle differential lock
The prado 90 provides for the possibility of rigid (some models have a self-locking LSD bridge). When it is blocked, 3 wheels start to rotate simultaneously, one in front and two in the back.
The inclusion of this lock is carried out by the “diff lock” lever from the instrument panel, and is driven by an electric motor mounted on the rear axle.
The cross-axle differential lock can only be engaged when the vehicle is stopped and the gear selector is in the N (neutral) position. The red indicator on the instrument panel lights up, first flashes (the locking process is in progress, you cannot move), then it lights up constantly (the lock is on). It is used for driving on mud, sand, deep loose snow, for greater cross-country ability (overcoming difficult areas). Cannot be used on hard ground. Can be used with low gear range.
Downshift gear
The extreme position (forward) of the handle of the transfer case includes a lower range of gears, which eliminates wheel slip and removes additional load from the engine and gearbox.
Can only be used with rear differential lock.
User Experience
From my personal experience, I can advise you to use these locks as little as possible. In the first year of operation, having no experience of driving on a permanent all-wheel drive, I believed that in winter it was better to use (for safety) a locking center differential. After replacing the razdatka chain, I no longer think so). Use locks only when really necessary, Prado on public roads and without it behaves quite steadily and confidently.
There are two modes H and L:
- H - normal mode
- L - reduced, the moment transmitted to the wheels increases.
- HH - normal driving
- HL - conventional with locking center differential, the moment is distributed between the axles 50/50
- LL - lowered with locking center differential.
To switch:
- stop the car
- press the brake pedal
- automatic transmission knob in N
- transfer handle in L
- Automatic transmission in D and you can go.
Exactly the same way back. Automatic transmission, depending on the goal, can be put in any gear.
The lowered one is turned on on a stopped car with the automatic transmission handle position in N, in the same way back. Blocking is possible while driving, while the electronics itself will determine the moment of inclusion, but it is advisable to turn it on before the start of dirt, sand, snow.
I turn on the reduced one very rarely, mainly when you need to carefully adjust the speed with the gas pedal (ruts, bumps, roads). In other cases, the moment is 4 liters. the motor is enough, except for very heavy mud or dense snow.
The center differential is locked by a lever next to the gearbox lever. The lock on the increased one turns on on the go, it does not connect immediately, it is recommended to play (easy) with gas or brake. Power-on indication on the panel, blinking - has not yet turned on or turned off, glows steadily, turned on. Turns off the same way. Reduced turns on, turns off ONLY when the machine is stationary.
The rear axle lock is activated on the go, the speed is less than 8 km.h. or on a stationary car, a switch on the front panel under the steering wheel. The lock is hard, ONLY for off-road. After turning on the switch, it is also recommended to play the gas-brake a little. Until the red indicator stops blinking and lights up steadily.
The owner's manual for the Prado says:
etlib.ru
120 Prado - How to change automatic transmission fluid | Page 4
I want to make a very important addition about the 5 speed 750th box. You need to control the temperature at a certain temperature using a scanner, or without a scanner, by switching the box to the ATF temperature control mode. Automatic transmission 5 st is switched to temperature control mode as follows: close the wiring 4 and 13 of the diagnostic block on the left under the steering wheel. (count from left to right, top row 1-8, bottom row 9-16 pins) Start the engine. Slowly move the gearshift lever from P to L and back to P. Quickly shift the gearshift lever from D to N and back 6 times. The OIL TEMP lamp on the instrument panel will come on for 2 seconds and then turn off. All the rules, remove the wiring and wait until the oil warms up at idle to operating temperature. You can move the selector to P, you can leave it to N. If the lamp is off, the oil is cold. The lamp is on - the temperature is normal, we climb to check the oil level on the car running. If the lamp flashes, the oil is overheated. Under the machine (on a running one), unscrew the control plug (hexagon by 5) if the oil does not pour out of it, add it through the filler (the filler on the right side of the car in the area of \u200b\u200bconnection with the razdatka, turnkey 24) until it flows from the control plug, how it stops pouring , begins to drip - we twist the control and filler and rejoice. After the engine is turned off, the box gets up on its own in normal mode. (I changed the ATF in the box 2 days ago, so, I filled it up according to the mapslow level, after running through all the gears I added it again according to the level, but when the oil warmed up until the Oil Temp lamp came on, it got in !!! 1.5 LITERS!) I copy-pasted my algorithm for self-changing oil in a 5 mortar: I bought spare parts: ATF-WS in one of the following packages, I took 3 flasks of 4 liters each. ATF WS 4L 08886-02305 ATF WS 20L 08886-02303 ATF WS 1L 08886-80807 Automatic transmission oil filter 35330-60050 Pan gasket 35168-60010 Automatic transmission oil filter gasket 90301-31014 Drain/control oil seal ring 2 pcs. It is also recommended to replace the rubber gasket of the filler plug, but I did not change it, I forgot to buy it. The tool is a 24 head for a filler plug, 14 for a drain plug, a 5 hexagon for a control one and a 10 head with a cardan and an extension (100 millimeters) for twenty pan bolts and 4 filter bolts. I was also helped by a hose for pumping gasoline with a pear, I filled it with fresh ATF, the end of the hose tightly into the filler hole, the second into a jar of liquid, and zhimk, zhimk pear, we pump, not a drop is spilled. Toyota's slurry packaging is such that you cannot fill it into a box without special equipment. Galosh gasoline or acetone a couple of liters for washing magnets and a pallet and a clean rag.I unscrewed the drain plug by 14. I drained everything that had merged - 2.5 liters. Dropped the pallet. By the way, all the liquid does not pour out. There is still a liter left in the pan. The filter is changing - (carefully when removing, do not pour over) another half liter is poured from the filter down the collar. After that, the magnets are washed from the pallet and the pallet itself from the metal suspension, and I had a decent amount of shit there, put the magnets in place and put a clean pallet on the new gasket. Tightening torque 4.4 Nm, do not overtighten! Wrap with two fingers, thumb and little finger, or even a screwdriver with a 10-inch adapter. The gasket is soft and shrinks very quickly, if you pull it all the way, it will squeeze out and flatten out. I put the drain plug on a new gasket. I fill in new fluid until it starts to ooze from the control plug. After that, the device will drive the most, for work at the service station. And I did it without a device in the garage. I threw off the ATF supply hose to the radiator, the upper one (located in the battery area) and this hose into an empty bottle. In general, it is better to increase the hose, otherwise it is short. The fitting on the radiator remains bare. I started it on P for 15-20 seconds, 1.5 liters of old blackening slurry was drained, it is not necessary to drain it anymore so that the box does not grab the air. Jammed. I added it to the filler according to the control level. And so 5 times until the clean slurry went to merge. Spent 10 liters of WSki. Then I heated the box in the service mode (description above) until the oil temp lamp came on, it warmed up by the way for about 50 minutes. After that, with the engine running, I added almost 1.5 liters more !!! until it poured from the control plug and that's it. I screwed it on a new gasket (the metal ring is crumpled) and you're done. Total spent 11.5 liters. Now the box is unrecognizable. Switches softer, thinks faster in kickdown. Well, the old one in color resembled working off the engine after 10 thousand km. Mileage before replacing ATF - 90k. Under my operating conditions, it clearly needed to be changed 20 thousand ago.
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prado-club.ru
120 Prado - How to change automatic transmission fluid
Re: Automatic transmission oil change and CE Prado-club on fire said: Ahem, Elchin, you're wrong. This is not a flushing fluid similar to the flushing oil of an internal combustion engine, but just an additive (another miraculous one), which requires REPLACING the automatic transmission fluid after its use. So the use of this chemical cannot be attributed to one of the methods for replacing automatic transmission fluid. Total, methods 2: complete replacement using special equipment and partial replacementI have an opinion - you can argue with hell: all these additives are evil. I strongly doubt that athletes use them on their cars (at least I have never heard from rally drivers)
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Here's another way for you...
quick and convenient draining of used oil and control of adding fresh oil;
a set of adapters allows you to service most car models
What is the MotorVac TransTech III used for? TransTech III is designed for a complete oil change in automatic transmissions of vehicles. TransTech III reduces vehicle maintenance time by performing a complete oil change (transmission oil change procedure takes about 10 minutes).
How does the MotorVac TransTech III work? Advanced electronic control allows the process of changing the oil in automatic transmissions at the touch of a button. The unit has a "drain into the sump" function, when a filter change is required along with the oil. TransTech III connects through the transmission radiator hoses and provides a "clean" process. The unit drains 100% of the used fluid and replaces it with fresh fluid in full while the engine is running. The most important thing in its work is that no adjustments or settings are required. TransTech III provides automatic control of the entire process. Usually, the process of changing the oil in automatic transmissions takes a long time and does not completely drain the used oil, and is also accompanied by constant spillage and contamination of both the car itself and the room. For example, a Toyota Land Cruiser Prado 95 with a 3.4 liter gasoline engine has an oil capacity in an automatic transmission of 12 liters. When replacing in the usual way, only 2 liters change! The converter, clutch drums, oil cooler, solenoids body are left filled with a large amount of used dirty oil, which will no longer retain its properties. With TransTech III, the process becomes simple and safe. And most importantly, the TransTech III installation changes the oil in the box quickly and completely.
Other Advantages of the MotorVac TransTech III The TransTech III has two other advantages over conventional oil changes in transmissions. A special cleaner, which is used when changing the oil, increases the life of the gearbox by removing wear products, metal particles and other impurities from the converter, cooling radiator, oil lines and the gearbox itself. A lubricating oil conditioner helps keep seals in good condition and does not crack, helps reduce the likelihood of leaks and overheating of the oil. This allows you to "extend the life" of the automatic transmission, get smooth and soft shifting and improve performance.
Pneumatic rear axle differential lock ARB for Toyota Land Cruiser Prado 120.
A common misconception is that four-wheel drive provides 100% traction - that is, that one necessarily accompanies the other. However, in reality, the wheels of most four-wheel drive vehicles slip when they get off-road. The problem is explained quite simply - one or more wheels lose traction with the road surface, and your standard center differential, which is designed for you to drive on a flat highway, sends all the power to those wheels that are spinning. On the road, a standard "open" differential allows each of your wheels to spin independently, completely disengaging the wheels from each other as they spin. Off-road, however, this becomes a major disadvantage, as engine power will go down the path of resistance, that is, it will be directed to wheels with little or no grip on the road surface. On new car models, a more modern design can be installed - a limited slip differential (LSD), which will behave "smarter" in the situation described above, however, most often you will not be able to continue moving forward with it, once in a difficult situation . Automatic locks also have their drawbacks: they can be very noisy when unlocked, and besides, they significantly impair the behavior of your car on the highway.
Pneumatic interlocks ARB provide 100% traction with the road surface when desired in any situation, without changing the behavior of your car on the highway. The pneumatic locks are controlled by a 12-volt compressor that activates and deactivates the absolutely reliable center differential lock. So you get traction when you need it at the touch of a button, while sitting in complete safety in your driver's seat.
Benefits of ARBs is a pneumatically controlled structure that is located inside the differential and, when turned on, blocks its action, stopping the rotation of the gears and, accordingly, stopping the effect of the differential on the axle shaft. When both wheels are "tied" directly to the rotation of the main pair, the car maintains the maximum possible grip with the road surface in all situations. In the unlocked state, the mechanism pneumatic lock ARB operates in the same way as a conventional differential. Besides the fact that pneumatic locks significantly increase the cross-country ability of an SUV, they also help to preserve natural resources. When a locked vehicle approaches a difficult section, it is not necessary to drive through it in an aggressive manner - "accelerating", relying on the momentum of the vehicle. With pneumatic locks, you can drive slower and safer, as grip on the road surface will be significantly improved.
