X-tronic CVT. Design Peculiarities. Pros and Cons. Typical Repair Issues and Useful Tips.

Today, many manufacturers equip their cars with continuously variable transmissions (CVTs). This transmission solution provides smooth change of the gear ratio parameter. Thanks to this peculiarity, CVTs have high efficiency and ensure maximum comfort while driving.

CVTs are actively produced by the world’s leading manufacturers of automatic transmissions: Aisin, Jatco, ZF. These companies cooperate closely with major automakers from the United States, Europe, and Japan. Thanks to the growing popularity of CVT transmissions, the company Nissan (or rather its subsidiary Jatco) designed a unique CVT and patented it under the name X-Tronic CVT. In this article, we will learn more about this transmission, analyze its pros and cons, and consider the main repair issues.

General Info

CVT is a stepless transmission which transmits torque from the engine to the gearbox. The main advantage of such mechanism is the capacity to choose the optimal ratio of working load and engine RPM speed. This provides the opportunity to maximize the engine efficiency and at the same time save fuel.

In the automotive industry, there are two main types of continuously variable transmissions:

• V-belt

V-belt CVT solution is a more common variation of continuously variable transmissions installed on front-wheel drive cars. This type of CVT is based on pulleys (driving and driven) and a drive belt. Pulleys are connected to corresponding shafts (input and output shafts).

• Toroidal

X-tronic CVT

The main goal of Jatco engineers during development of the X-tronic CVT was to reduce fuel consumption and decrease operation noise which was the cause of frequent complaints from owners of Nissan cars equipped with CVTs.

In fact, X-tronic is a modified version of the V-belt CVT transmission. According to the manufacturer, X-tronic doesn’t have typical CVT faults. This peculiar transmission is intended for cars with the engine capacity from 2 to 3,5 liters. The X-tronic CVT is mainly installed on Renault (Kaptur, Fluence) and Nissan (X-trail, Murano, Maxima, Juke, Pathfinder, Altima, Quest, Sentra, Note). According to Renault representatives, installation of the X-tronic in Renault Kaptur helped to reduce fuel consumption by 12% and to decrease friction coefficient to 40 %.

Check out great videos about X-tronic CVT from Nissan

CVT X-tronic has a number of peculiar design solutions:

• Changed design of pulleys and the transmission belt introduced by Jatco engineers. Pulleys in X-tronic were made thinner, and the belt was constructed with the help of aluminum, which reduced its flexibility. The compact and efficient oil pump allowed engineers to increase reliability of the transmission by pressure reduction between the pulleys and the belt;
• Lower level of operation noise in comparison with other CVT solutions used in Nissan cars;
• Reduced viscosity of the required transmission fluid. This measure resulted in excellent anti-friction performance and reduction of transmission parts wear-out;
• Smaller weight and more compact design in comparison with its predecessors ;
• Adaptive Shift Control system which helps to adopt the transmission to different operation conditions;
• Novelty additional planetary gear introduced in X-tronic. This solution ensures increased gear ratio (7.3/1) compared to conventional CVTs.
• Possibility to pair X-tronic with powerful IC-engines without any loses for its operating resource.

In practice, owners of cars equipped with the X-tronic transmission note that this transmission operates quietly even at low engine RPM, has great acceleration characteristics, ensures maximum comfort and fuel economy.

Despite numerous advantages, the X-tronic transmission has its drawbacks:

• Slippage while driving on snowy or muddy roads;
• High cost of maintenance and repair;
• In case of serious failures, the only repair option for CVT X-tronic turns out to be the complete transmission replacement;
• X-tronic is extremely sensitive to overheating. Thus, cars with this transmission won’t be suitable for drivers with aggressive driving style. Repair specialists also recommend installing an additional cooling system in order to prevent transmission overheating;
• X-tronic is very sensitive to non-compliance with the rules of operation. If drivers disregard recommendations specified in the manual, it will certainly lead to the transmission failure;
• X-tronic (like all CVTs in general) is less dynamic than manual or semi-automatic transmissions. For this reason, the process of acceleration takes a bit more time.

Service life period and possible malfunctions

On most vehicles, the service life of X-tronic approximately reaches 150,000 kilometers. During this time, drivers should not experience any problems with the transmission. Car manufacturers guarantee uninterrupted operation during the service life period depending on the car model (under the condition that drivers follow rules of operation). After 150 thousand kilometers, car owners can face the following typical X-tronic problems:

• Some car owners complain that when they slow down the speed below 20 km/h, the car starts moving with jerks;
• If drivers frequently violate rules of operation, the X-tronic transmission becomes much noisier. This problem may have numerous causes, thus a proper diagnostic is required;
• Damage of the drive belt. Over time, the belt wears and tears down. Metal particles from the damaged belt can affect other structural elements of the transmission;
• Bearing failure which is accompanied by abnormal noises.

On the basis of the above, we can conclude that CVT transmissions are suitable for drivers with calmer and more reserved driving style. As for the X-tronic transmission, Jatco engineers managed to reduce the level of operating noise by increasing the gear ratio parameter and to enhance its productivity and efficiency in terms of fuel consumption.

X-tronic vs. Automatic transmission

Moreover, the manufacturer says that the X-tronic transmission has an increased operational resource; this transmission can withstand overloads and is intended for pairing with more powerful engines. In other words, X-tronic can operate at high RPM speeds and copes well with high torque. In addition, the ECU of this transmission has a several adaptive modes (city, highway, sport mode, etc).

In practice, however, you should not expect that the X-tronic transmission will radically differ from other CVTs, despite increased reliability and a range of other improvements. In other words, if you don’t want to face premature transmission repairs, it is necessary to do the following:

• Do not drive at high RPM speeds;
• Avoid slippages;
• Try not to overload the car by transportation of cargo or towing a trailer;
• Monitor the level of transmission fluid;
• Do not practice sudden accelerations from a standstill.
• Monitor the operating status of sensors and controllers implemented in the transmission. CVT transmissions have a large number of electronic units in their design. If one sensor gets out of order, it may entail the failure of the whole unit. The transmission can go into limp mode.

Tips on driving cars with CVT transmissions

Complaints about unreliability of this transmission are frequently caused by the fact that drivers do not follow rules of operation specified in the manual. Before buying a car equipped with the X-tronic transmission, you have to understand whether operational capacities of this transmission correspond to your driving style. It is important to remember that the cost of the X-tronic transmission repair is very high.