Removing the gearbox from Nissan Almera is an operation that requires not only physical effort, but also a deep understanding of the design of a front-wheel drive vehicle. Most often, this step is resorted to when replacing a release bearing, repairing a gear selection mechanism, or replacing differential seals. Do not underestimate the weight of the unit: even empty manual transmission weighs enough to cause injury or damage to the body if handled carelessly.
The process of removing the assembly Nissan Almera (especially G15 models with the H4M engine) has its own specific features that differ from similar procedures on other Japanese cars. For example, the location of the mounting bolts and the need to remove the subframe can be a stumbling block for a newbie. Proper preparation of the workplace and the availability of specialized tools will reduce risks damage to neighboring units.
Preparation of the workplace and necessary tools
Before getting under the car, you need to make sure you have all the necessary equipment. The absence of even one key can turn the removal procedure into hours of agony. To work with Nissan Almera you will need a set of sockets, including extensions and universal joints, since access to the box mounting bolts is often limited by other suspension parts.
Pay special attention to the jack and support posts. You need to lift the car on a lift or use reliable stands under the body, since you will be under the car for a long time. You will also need a hydraulic jack with a wide platform or a special transmission dolly to support the unit while removing the last bolts.
- 🛠 Set of socket heads from 8 to 22 mm with extensions
- ⚙️Hydraulic jack for support gearboxes
- 🔧 Retaining ring remover and pry bar
Do not forget to prepare a container for draining the oil, since when dismantling the unit, some of the transmission fluid will inevitably leak out. It is also recommended to stock up on rags and carburetor cleaner to clean the surfaces before starting work.
⚠️ Warning: Never work under a vehicle that is supported only by a jack. Be sure to use safety stands under the sills or side members.
Removing suspension elements and exhaust system
The first stage of work is to free up the space around Manual transmission. Start by removing the wheels and engine guard, if installed. Next, you need to dismantle the exhaust system elements that are attached to the box or subframe. On Nissan Almera Often you have to unscrew the exhaust pipe from the exhaust manifold, which requires considerable effort due to soured bolts.
The next step is to disconnect the wheel drives. This is a critical point, since without removing the drives from the hubs it will be impossible to lower the subframe or remove the box. Use a pry bar to carefully remove the splines, being careful not to damage the axle seals. If the drives cannot be removed, check the condition of the retaining rings.
- 🔩 Unscrew the bolts securing the exhaust pipe to the manifold
- 🚗 Remove the front wheels and disconnect the drives from the hubs
- 🔧 Remove the speed sensors and crankshaft position sensor
After removing the exhaust system and drives, you need to disconnect the gearshift cables. On Nissan Almera The gear selection mechanism can be made in the form of rods or cables that are attached to the lever on the box. Disconnect them carefully, remembering the location, so that during assembly there will be no problems with selecting gears.
- Front
- Full (rare)
- Rear (modification)
- I don't know
Disconnecting electrical and hydraulics
The electrical part of the job often raises fewer questions, but requires care. It is necessary to disconnect all connectors going to the gearbox. This includes the speed sensors, crankshaft position sensor (if located on the transmission housing), and starter wiring. On Nissan Almera wires are often laid in such a way that they are easily damaged during rough dismantling.
If your vehicle is equipped with a hydraulic clutch, you will need to disconnect the slave cylinder from the transmission. It is not necessary to drain all the fluid from the system, just unscrew the tube and plug it with a clean plug to prevent dirt from getting into the hydraulics. The cylinder itself can be hung on a wire so that it does not interfere when removing the unit.
- 🔌 Disconnect the negative battery terminal for safety
- 🔋 Remove the connectors from the speed and crankshaft position sensors
- 🛢 Disconnect the clutch slave cylinder from the crankcase
Pay special attention to the starter. It is often secured with bolts passing through the transmission housing. Unscrew these bolts and carefully move the starter to the side, disconnecting the power cable from it. Do not place the starter on the ground as this may damage the starter housing or wiring.
⚠️ Attention: Before disconnecting the wires, be sure to photograph their location to avoid errors during reassembly.
☑️ Preparation for removing the manual transmission
Loose subframe and engine mounts
This is one of the most difficult stages of work. On Nissan Almera for complete dismantling manual transmission It is often necessary to lower the front suspension subframe. To do this, you need to loosen the bolts securing the subframe to the body, but do not unscrew them completely. The subframe is also supported by engine mounts, which must be removed.
First remove the engine mount from the transmission side. This will allow the engine to move slightly. Then, using a jack to support the subframe, slowly unscrew the bolts securing the subframe to the body. Lower the subframe to a safe height to gain access to the lower transmission mounting bolts. Be careful not to lower it too much to avoid damaging the brake lines and tie rods.
- 🔧 Unscrew the bolts securing the right and left engine mounts
- 📉 Slowly lower the subframe, controlling the tension of the hoses
- 🔩 Unscrew the bolts securing the subframe to the body
After lowering the subframe, access to the lower bolts securing the clutch housing to the cylinder block becomes visible. On Nissan Almera these bolts are often hidden and require the use of extensions and universal joints. Make sure that the engine is securely supported so that it does not fall along with the subframe.
Why do you need to lower the subframe?
The bolts securing the gearbox to the cylinder block are often located so that access to them is blocked by the subframe. It is impossible to unscrew them without lowering it.
Direct dismantling of the unit
When all fasteners are freed, you can begin the final stage of removal. Place a hydraulic jack or dolly under the transmission housing to support its weight. Start unscrewing the remaining mounting bolts gearboxes to the engine block. Do this evenly so as not to distort the unit.
After unscrewing all the bolts, carefully move the box away from the engine, making sure that the input shaft does not damage the crankshaft seal. Move the unit strictly along the axis, avoiding distortions. If the box gets stuck, use a pry bar to carefully separate the surfaces of the crankcase and block. Do not use excessive force to avoid damaging the aluminum housing.
- 🏗 Support the gearbox with a jack when unscrewing the last bolts
- 📐 Move the unit strictly along the axis, avoiding distortions
- 🚚 Carefully lower the box onto the pallet or cart
Once the unit is disconnected from the engine, it can be completely lowered and rolled out from under the vehicle. Make sure the floor is free of oil and tools to avoid injury when moving a heavy unit. It is recommended to place the removed box on a flat surface and plug the holes to prevent dirt from getting inside.
Before removing the box, mark with a marker the positions of bolts of different lengths so as not to mix them up during assembly, as this can lead to oil leaks.
Bolt tightening table and specific torques
When reassembling, it is extremely important to observe the tightening torques of the gearbox mounting bolts. Violation of these parameters can lead to vibrations, oil leaks, or even the destruction of threads in the aluminum block. Below is a table with recommended tightening torques for the main connections on Nissan Almera.
| Fastening element | Thread diameter | Tightening torque (Nm) |
|---|---|---|
| Bolts securing the gearbox to the block | M10 | 45-55 |
| Subframe bolts | M12 | 80-90 |
| Engine mount bolts | M10 | 50-60 |
| Starter mounting bolts | M10 | 35-45 |
Pay special attention to the condition of the clutch housing gasket. When removing Manual transmission an old gasket almost always becomes unusable. Never try to reuse it, as this is guaranteed to lead to oil leakage and dirt getting into the unit. The use of sealant instead of a gasket is allowed only in emergency cases and is not recommended by the manufacturer.
Also check the condition of the clutch basket damper spring and the disc itself. If you removed the box to replace the bearing, it often makes sense to immediately replace the clutch, since repeated dismantling is a labor-intensive process. Make sure the input shaft splines are clean and free of burrs.
Maintaining correct transmission mounting bolt torques is critical to preventing future vibrations and oil leaks.
FAQ: Answers to frequently asked questions
Do I need to remove the subframe completely or is it enough to lower it?
It is not necessary to completely remove the subframe. It is enough to loosen the mounting bolts and lower it 10-15 cm to provide access to the lower gearbox bolts. Complete removal will complicate the assembly process and require adjustment of the suspension geometry.
Is it possible to remove the box without draining the oil?
Technically possible, but highly not recommended. When the box is disconnected, the oil will flow out uncontrollably, which will lead to its loss and contamination of the engine compartment. It is better to drain the oil in advance through the drain hole.
What to do if the gearbox mounting bolts are stuck?
Use a penetrating lubricant (such as WD-40 or similar) and let it sit for 15-20 minutes. If the bolt does not budge, you can gently heat it with a hair dryer, but avoid open flames and overheating of aluminum parts.
Do I need to remove the starter before removing the box?
Yes, the starter must be removed or at least unscrewed and moved to the side, since it is often attached to the gearbox housing and blocks access to the fasteners.