04 Juin.
Advice and maintenance

How do I know if a gearbox is out of order?

The components of a car mechanic are mostly wearing parts. The maintenance booklet therefore specifies the frequency with which the components in question must be replaced. For example, shock absorbers must be replaced every 80,000 km, brake pads have an average life of 30,000 km, etc.

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Gearbox failure: what are the indicators?

The robustness of the gearbox is astonishing. For all makes and models, this transmission component should theoretically last as long as the car! In practice, however, a few factors can distort this estimate. Most often, these are unexpected circumstances such as shocks and accidents, but they can also be the consequences of careless mistakes such as forgetting to carry out regular servicing and maintenance. As a result, the performance of the gearbox declines. At first, the problems are minor, but they can develop very quickly. If you do not react to the first symptoms, there is a risk that the components will break and the gearbox will be completely unusable. In the latter case, you should consider going to a specialist shop to find a replacement box compatible with your car. But before you get to that point, you can pay attention to the signs of trouble.

The following faults and symptoms are those considered to be recurrent. Other, less frequent faults should not be ruled out. At the first sign of trouble, i.e. as soon as your gearbox changes its behaviour, you should have it checked quickly.

You may feel that the gearbox has become hard. This is not necessarily a symptom of a breakdown, but it is still essential to carry out a few checks. First check the clutch pedal to make sure that its travel is not impeded by rubbish, gravel, mud, a thick or badly positioned floor mat, etc. Is the problem persistent? Check the oil level in the gearbox. When there is not enough liquid, the gears are poorly lubricated and you have to force the gearbox to react to your movements. At the same time, check the clutch fluid level. If you are not comfortable with these checks, ask a professional to do them.

You may feel that several or all gears are hard. They shift with difficulty.Worn timing rings and linkage problems are often to blame. As the parts are worn, they are no longer able to carry out their function, which is to transmit the lever command inside the gearbox to engage the desired gear. The hardness of several gears can also be the result of a failure of the flywheel or the clutch system.

There is only one gear that shifts badly. This means that one of the parts connected to the gear concerned is out of order. This is usually the synchro, but be aware that other components may also be the cause of the problem.

Your gear engages normally but tends to engage by itself, especially when you accelerate. The gear lever moves back into neutral without any intervention from you. This means that the gear 'jumps', which is often the result of a linkage or synchro failure.

You hear a kind of whistling sound from the gearbox as the engine speed increases. If the noise disappears on disengagement, it is probably a sign that the bearings are worn. It is these parts that need to be replaced, not the entire gearbox.

Cracking noises are always heard when you shift gears. This may or may not be associated with difficulty in engaging gears, but in most cases it is a sign of worn synchros. Gear shifters can also make a cracking noise when the cables are incorrectly adjusted.

You may notice a whirring sound when you are in certain speed ranges. It is possible that the sprocket teeth are too worn.

When you accelerate, your gearbox makes an unusual noise. The noise may also occur when you are in engine braking. In these cases, it is likely that the problem is with the differential.

Oil may be visible under the gearbox housing. If you notice stains where you parked, this indicates an oil leak. The housing may be punctured or poorly sealed. At first, you may not notice any suspicious noises or signs of low fluid. But if you let the problem linger, there is a high risk that the gearbox will eventually break. Never take a leak lightly!

As stated at the outset, these are the most common manifestations of an anomaly in the how your BV works. If you notice one or more of these warning signs, but also if you notice other abnormal signs, it is best to stop using the car. The best thing to do is to call a professional and make an appointment to have the gearbox diagnosed.

Gearbox out of order: how to repair it?

It goes without saying that any faults must be properly repaired. Otherwise, you will not be able to continue driving your vehicle without the risk of aggravating gearbox failures. Stay calm and be methodical. The first thing to do is to note all the symptoms. Then contact a professional mechanic and tell him about the signs of failure you have noted. They may advise you to take the vehicle to their workshop or have the car towed/towed if the symptoms are likely to indicate critical faults.

Once your vehicle is in the hands of the mechanic, he can start the checks. No part escapes his attention.

Removal is often necessary to refine the diagnosis. In other words, the mechanic removes the gearbox and examines it on a clean workbench. The removal of the gear box depends on the transmission system. If your car has front-wheel drive, the gearbox may be located in front or behind the engine. Various components will need to be removed to access the gearbox. In some cases, the grille, the power unit, the radiator, etc. must be removed. If your car has a rear-wheel drive transmission, the gearbox is usually removed from the passenger compartment or from underneath. Depending on the model you drive, the removal of the engine may also be necessary for the mechanic to safely remove the gearbox.

The gearbox is usually changed before removal. If necessary, the mechanic removes the oil after placing the gearbox on his work surface. The entire outer surface of the gearbox is then thoroughly cleaned. This is done with a brush dipped in petrol or diesel fuel or with a steam cleaner.

Once the gearbox is removed and drained, the mechanic can begin disassembly to access each part for inspection. The mechanic will probably rotate the driveshafts to assess the degree of wear of the gears. He will also check that the teeth of the pinions are complete and in perfect condition. At the same time, he will inspect the bearing surface of the gearbox, which should be free of pitting. This inspection continues until all the components of the gearbox have been thoroughly checked. Are there any gaps or are the parts correctly attached? Are the seals still in good condition? Are all the screws present and, if so, are they performing their functions correctly? Are the parts pierced, cracked, etc. or do they show other forms of deterioration?

As the mechanic assesses the gearbox, he lists the defective/worn components such as synchro rings, bearings, etc. He notes which ones need to be replaced and which ones are recommended. He notes which ones must be replaced and which ones are recommended for replacement. Depending on the results of the diagnosis, the professional can conclude whether the gearbox needs to be replaced.

Before considering its replacementBefore considering a replacement, you need to know the gearbox number to ensure that you buy a compatible product. Your garage will be able to give you this information.

Once you have found a compatible gearbox, the mechanic can proceed with the reassembly, which is as complex as the removal. Gearbox, secondary shaft, seals, oil pan... each element is inspected and fixed with great care. The assembly is carried out in an order specific to your gearbox. As during removal, the mechanic may touch other mechanical components so that the gearbox is installed in the correct manner. The next step is to lubricate the gearbox, which involves adding a gearbox oil with a viscosity index in accordance with the manufacturer's recommendations. After that, the garage owner starts testing. He makes sure that the gears are turning properly. He checks that the gears shift smoothly and quietly. He checks that there are no lubricant leaks. Other checks will obviously be carried out, which requires meticulousness, a great deal of rigour and an impeccable command of the gearbox mechanism.

Automatic transmissions are more than just mechanical parts. The mechanic must check that the electrical and electronic functions are normal. A complete reprogramming is usually necessary before the gearbox is ready to take over its functions.

It is only after this series of methodical checks and tests that the mechanic will be able to give you back a functional gearbox. His intervention is subject to a guarantee that will allow you to drive thousands of kilometres with complete confidence.

Before setting off again, remember to find out what maintenance is required and how often. Don't forget that taking care of your gearbox is the best way to avoid breakdowns! Also ask your garage if they have any additional recommendations for preventing malfunctions.

Gearbox out of order: where to find a replacement part?

You have now passed the first step inbuying a gearbox, which is to find out what part number you are looking for. You can then start to compare existing offers, taking care to avoid pitfalls. When a gearbox breaks down beyond repair, you will have to pay quite a lot for a replacement. It is understandable that you should look for affordable parts first, but this should not be at the expense of product reliability. As we have already mentioned, a gearbox should last as long as your vehicle is used. It should be operational for at least a few hundred thousand kilometres. That's the whole point of choosing a quality gearbox.

The choice of shop is extremely important. Make sure you use a platform that exclusively offers gearboxes that have been tested by experts and are subject to a parts warranty. These criteria are among the priority commitments of the EDEN BOITES team. Each of the 12,000 products available in our 7 storage centres has first undergone a series of checks. Our technicians ensure full performance, regardless of the range to which the product belongs.

As an entry-level product, we offer used gearboxes. By definition, these are mechanical components that have previously been used in other vehicles. However, these manual and automatic transmissions are always reliable. After their evaluation, our specialists define the warranty period, which is at least 3 months, but can be longer depending on the characteristics of the used product. This product family is mainly suitable for vehicles that are not subject to heavy use.

The range is increased with standard exchange gearboxes. The prices are higher but the guaranteed performance is also better. This product category comes with a 12-month warranty and is perfectly suited to intensive use. In other words, it is better to invest in a BVM or BVA in standard exchange if you are used to long journeys and/or if you drive the car regularly.

We take care to regularly replenish our stock, ensuring that a wide range of products is available to our customers. Despite this, the possibility that the product you need is not in stock is not ruled out. Rest assured, we have an excellent alternative that allows you to reduce your expenses, fight waste and enjoy a like-new gearbox. This is the 0 km rebuild of your defective part, which is simply called gearbox reconditioning. Your garage will change the oil, remove the gearbox and secure it on a pallet. Our team takes over and organises the removal, rebuilding and return of the reconditioned product to you.

EDEN BOITES has a leading position on the French market and also on a European scale. This is primarily due to the rigorous attention we pay to the quality of our gearboxes, without neglecting our application to offer competitive prices thanks to which you can control the costs of the repair. Add to this the fact that we operate on a continent-wide basis. This means that you can specify a delivery address in France or in another European country, and we guarantee that your gearbox will be delivered as quickly as possible by carriers who are experts in their field.

Don't wait until your gearbox is more serious to ask for your free quote. You will quickly receive a personalised, no-obligation quotation by return e-mail. Are you happy with the proposal? Confirm your order and take advantage of the many secure payment solutions we offer. Your gearbox malfunction will soon be a bad memory and you will be able to take to the road again with peace of mind.

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