Issues addressed in the material:

  • Why do I need oil in the gearbox
  • When is the gearbox oil replaced?
  • What type of oil to put in the gearbox
  • Preparing for an oil change in the axle gearbox
  • How is the gearbox oil replaced?
  • Experienced opinion on changing the gearbox oil

Changing the oil in the gearbox prevents increased friction of the elements, which occurs as the loss of its lubricating properties. The gearbox is mounted on the front axle of the front-wheel drive cars (in this case it is integrated into the gearbox), on the rear axle of the rear-wheel drive cars and on both axles, when it comes to all-wheel drive cars. Thanks to this unit, torque is received from the crankshaft and its subsequent transmission to the center differential.

Since the torque is transmitted by the gearbox with the help of gear gears, it is they that eventually wear out. In order to prevent it and protect your car from breakdown, it is necessary to timely change the gear oil in this unit. We will talk about how to replace the lubricating fluid in the gearbox in this article.

Why do I need oil in the gearbox 

transmission

The main task that the lubricant performs in the gearbox is to reduce friction during the operation of this mechanism. A dense oil film forms on all of its elements. This eliminates the abrasion of parts, which means that the gearbox will work properly for a long time.

Why lubrication is still needed:

  • The liquid prevents rust from forming, protecting metal surfaces from oxidation. As a result, the resource of the mechanism increases.
  • Lubrication does not allow parts to overheat, because it absorbs part of the thermal energy, as a result, the gearbox cools.
  • Cleans the unit of dirt and chips. The lubricant contains additives that bind microparticles of dust and dirt that penetrate the mechanism. The effectiveness of additives will be the higher, the better the lubricant composition.
  • Lubrication allows the motor to start easily even in severe frosts. Due to low temperatures, the metal elements freeze, and parts stick together. If no oil is poured into the mechanism, the engine will not start. The fact is that the gearbox will stall, as a result, the crankshaft will not be able to start moving. Avoid this transmission grease, it will not allow the parts to stick together.

The better the lubricant, the higher its effectiveness. Please note that when changing the oil in the gearbox, use a regular transmission fluid. It is also used in the gearbox. However, it is recommended that you still check the data that is listed in the service book of the car. In rare cases, special grease should be added to this mechanism. Also, do not forget that engine oil cannot be poured into the transmission. The fact is that the viscosity, temperature and composition of these lubricants is different.

When is the gearbox oil replaced?

changing gearbox oil

When to make an oil change in an automatic transmission gearbox? It is impossible to give an exact answer to this question. Usually, the grease is changed to a new one when servicing the transmission, when other working fluids are filled. Maintenance of the box should be done every 45,000 kilometers (or every 60,000), that is, once every two years.

However, the oil in the gearbox should be replaced more often if the machine is operated intensively, as in the following cases:

  • you carry heavy loads, tow trailers or cars on a cable;
  • the machine is used in difficult conditions, for example, you drive off-road, in deep snow;
  • drive in the city, often stand in traffic jams.

If you have a new car, then having studied the operating instructions, you can find out that the manufacturer recommends performing the first oil change in the engine gearbox after 1,000–2,000 kilometers. Indeed, at this time, all the mechanisms of the car are ground to each other, which means that during this period the friction will be increased and a large number of wear products will form.

If you do not change the oil regularly, it will lose viscosity. Then oxidation processes will begin due to the fact that hot air enters the depressurized system. All this will lead to decomposition of the working fluid, it will cease to properly lubricate the parts. As a result, the gears wear out and the gearbox starts to overheat.

What type of oil to put in the gearbox

When changing the oil, select the standard transmission fluid recommended by the automaker in the operating instructions for your machine. In the case when it is not at hand, and you do not know exactly what grease can be used, classification according to API, as well as viscosity should be taken into account.

Most car manufacturers recommend replacing the gearbox oil with new cars using GL-4 or GL-5 gear oil. These greases contain special additives that prevent scuffing. How to determine what viscosity should be? In this regard, the climatic conditions in which the vehicle is operated should be taken into account.

To replace the oil in the transmission, it is recommended to take all-weather lubrication, because no driver will begin to fill in new working fluid every season. On all-season lubricants there will be double numbering, for example, 75W-90. In this marking, 75 means viscosity at sub-zero temperatures, 90 means viscosity in the warm season. If you need a working fluid that can withstand severe frosts, then choose oils with a label where the first digit will be less. Such a lubricant will retain viscosity even at low temperatures. For example, 70W is suitable for operation at 55 ° C below zero, 75W at -40 ° C, 80W at -26 ° C.

How much fluid do you need to replace? If you have a front-wheel or rear-wheel drive car, 1-2 l of grease will be enough. When the car is four-wheel drive, with two crankcases, it is better to purchase 3 liters or even more. To replace the grease in a utility vehicle, 10–15 L of oil will be required. Experts recommend that you always have 1 liter of liquid in reserve, because it is likely that you will need to flush the mechanism.

Preparing for an oil change in the axle gearbox

If you plan to do the oil change in the gearbox and “razdatka” by yourself, adhere to the following rules:

  • Securely secure the machine. Put it on the hand brake, stoppers should also be put under the wheels.
  • The transmission must be warmed up before you begin the replacement. Make sure that the gearbox is not hot. Be careful, the grease should not get on the skin, otherwise you may get burned.
  • You should change into old clothes in which you will be comfortable working. You should not be wearing synthetic clothing, because if it lights up, it will stick to your skin.
  • It is necessary to wear special protection so that the grease does not get into the eyes, nose and mouth, otherwise a mucous burn will occur.

What will be required to replace the oil in the steering gear:

  • wrenches, the set must include ring spanners, spanners, as well as hexagons;
  • a set of screwdrivers, you will need a flat, cross-shaped, and also with a cross-section “torx”;
  • WD-40. This composition will be required to clean the screws and cork;
  • container in which you will merge old grease. Its volume should be slightly larger than the amount of working fluid in the mechanism;
  • a syringe, as well as a hose, with the help of which the oil in the gearbox will be replaced. Instead, you can use a hose of sufficient length and a funnel;
  • lift or inspection hole, where you will perform the replacement.

First of all, prepare and then check the level of the working fluid. And you have to do this without using a probe. Checking is done using the filler hole. Ideally, the level of lubricant should be 0.2–0.5 cm lower than the hole. It is recommended to make a probe with your own hands, it can be used for verification. Also pay attention to the shade of the grease and how thick it is. What color of working fluid can be:

  • the grease is clean, its shade is exactly the same as the new oil or a little darker. In this case, a replacement is not necessary, since the working fluid has not deteriorated;
  • the oil is dark and clear. There are no extraneous inclusions. What to do in this case? If the time has come, then you should make an oil change in the gearbox, if not, then it is allowed to replace it later;
  • the grease is dark and cloudy, you can see microparticles of dirt and metal powder. Replacement should be carried out, even if the deadline has not yet come. Flushing the mechanism is also recommended;
  • oil thickened and darkened. You can see metal shavings. Lubricant change required. Moreover, it is also necessary to diagnose the mechanism, possibly repair it. It is necessary to do these procedures in a specialized car service.

How is the gearbox oil replaced?

The first step to starting the oil change is to warm up the gearbox. Motorists with extensive experience are advised to drive about 5-10 kilometers. Then you need to park the car and get to work.

1. Drain the used oil 

fluid leaking out gearbox

How to change the oil in the front gearbox? To do this, remove the crankcase guard. All bolts must be flushed and then applied with WD-40. The gearbox also needs to be cleaned of contaminants, remove corrosion. Traffic jams can also be treated with WD-40. The fact is that most often they sour, therefore, unscrewing them, you should be careful. Otherwise, you will tear the thread.

Under a drain hole it is necessary to substitute a container of large volume into which liquid will merge. Now you can unscrew the drain plug. As soon as the grease starts to leak, unscrew the filler cap. Now you need to wait until all the liquid has drained out.

2. Flush the gearbox

Sometimes it is better to use a special tool for washing. However, oil is most often used for this. How to flush:

  • We collect grease into the gearbox through the filler hole. This can be done using a syringe to which a hose of the required length is connected. The hose should be chosen so that it fits tightly on the syringe and passes into the filler hole. The amount of lubricant is 70–80% of the norm.
  • Close the filler hole. Now you need to drive a car along the highway 15–20 kilometers to break in the mechanism. Running-in means smooth movement, no need to sharply switch speeds.
  • Next, remove the liquid, how to drain it, it was described in the first paragraph.
  • We study the merged grease, pay attention to its color and density. If necessary, wash again.

Filling is performed using the same technology as previously described. To find out how much fluid is needed, read the car’s instruction manual. Typically, the level of lubricant should go to the bottom of the filler hole or be slightly lower. After that, carefully twist the filler plug. Note! If the plug is tightened badly, dirt will enter the mechanism.

When the replacement is completed, the machine should be run in for 2-3 days. After this time, check the lubrication. If it is in good condition, then you did everything right.

If the oil in the gearbox is not replaced in a timely manner, the mechanism will quickly fail, and driving the car will be unsafe, because a malfunction of the unit leads to the risk of an accident. 

Experienced opinion on changing the gearbox oil

  1. Does the manufacturer advise changing every 100 thousand? Repair pros recommend every 80k.“I did an oil change in the rear axle gearbox in a car service after 100,000 kilometers, as the automaker recommends. However, specialists at the service station advised doing this every 80,000 km. I believe these guys have never failed. I do not advise changing the lubricant in private car repair shops, because no one will guarantee that such a master knows how much fluid to fill. ”
  2. Need to change the gearbox oil? Check the pharmacy first“I skated 83,000 km, drove a car for 6 years. When the time came, I did the oil change in the rear gear with my own hands. A total of approximately 550 ml of grease was required. Poured from a four-liter canister, so I can not say the exact volume.

    Replacement made at the cottage, there was no overpass, no lift. Auto put on a stand (17 cm height). Filling the grease – the procedure is simple, the price of changing the oil in the gearbox is minimal, because the cost of lubrication is small. And you don’t have to pay for work, because I did everything myself.

    Not sure how to fill in the liquid? Take the syringe to Janet. We put on a flexible nozzle on it, the length is about 20 cm. 160 ml enter the syringe, I filled in about three and a half syringes. “

  3. Three-liter “razdatka” in another place“If the car has a 3 liter engine, then the“ razdatka ”will be located next to the right front wheel. In this case, it will not be easy to get to the filler bolt. The automaker made an “OIL” mark on the head of the filler hole bolt to make it easier to navigate when replacing. The replacement was carried out after having previously studied the book from the Third Rome Publishing House, if desired, it can be downloaded, as it is freely available. “
  4. If the oil in the gearbox has not changed, carefully fill in new oil.“A friend of VAZ 4, in the checkpoint, no one ever changed the lubricant, but there was no buzz in the bridge. When I decided to change the old fluid, it was as thick as a solid oil. After the replacement, he skated 2,000 km, and the gear began to buzz. In the car service, the guys said that in such cases, when no one ever filled a new lubricant, the replacement should be carried out in several stages: first we merge a quarter, add a new lubricant. And how he did it: he removed all the dirt that had clogged into every crack and crack with new oil. And all the holes were exposed again. ”
  5. Do not change “cold” oil in the gearbox“How to replace: weaken the drain nut, tighten it. Then you need to ride a car 10-15 km, then remove the grease. The heated liquid will merge faster. After that, inspect the filler plug. It needs to be checked in advance, perhaps it has become attached, and it will be problematic to unscrew it. ”’

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