ON THE COVER

Continuously Variable Transmissions

Nissan^® refreshed and modernized the Continuously Variable Transmission (CVT) and in 2002 became one of the world’s first automotive manufacturers to include CVTs in passenger cars. Nissan has continued building and improving CVTs and today has millions in operation with applications spanning from mini-vehicles through to 3.5-liter class, full-size sedans.

CVTs have been described as single-speed, gearless transmissions or as one-speed automatic, variable-pulley transmissions. They are designed to change seamlessly through an infinite number of effective gear ratios between maximum and minimum values with the use of variable diameter pulleys. A Continuously Variable Transmission transmits power by means of these pulleys and a high-strength steel belt instead of fixed gears. One pulley receives the power generated by the engine and the other pulley transmits the drive power to the wheels.

Both pulleys have V-shaped grooves in which the connecting belt rides. One side of the pulley is fixed; the other side is movable, actuated by a hydraulic cylinder. When actuated by various sensors, the cylinder can increase or decrease the amount of space between the two sides of the pulleys. This allows the belt to ride lower or higher along the walls of the pulleys, depending on driving and road conditions, thereby changing the gear ratio. The gear ratio varies continuously rather than in steps, which contrasts with other mechanical transmissions that offer a fixed number of gear ratios.

When an automatic transmission shifts gears, engine RPM rises above or falls below the engine’s optimum power and efficiency range. Xtronic^® CVT continuously adjusts the transmission’s output to keep the engine in its optimum power and efficiency range at all times. This means immediate acceleration for passing because there is no waiting for the transmission to downshift.

CONTENTS

Overview

Continuously Variable Transmission (CVT)

CVT List

CVT Control System

CVT Story RE0F10D

New Generation Xtronic CVT

Next-generation Xtronic CVT

CVT Story RE0F02H

Xtronic CVT Shifting

CVT Service Tips

CVT Transmission Oil Warmer

Towing and CVTs

Moving Up - Masters and Seniors

PUBLISHING & TECHNICAL EDITOR/ART DIRECTOR

Richard Beaumar

MANAGER

Richard Daniels

CONTRIBUTING EDITORS

TWEDDLE GROUP

DESIGN/PRODUCTION

TWEDDLE GROUP

Special thanks to our contributors for this issue:

NORM AMMERMAN

Technical Publications

ROB BARTO

Technical Training Design

CHRIS BURKE

Bosch Automotive

LINDA CHEN

Field Quality Investigations

GREG CHRISTENSEN

Technical Publications

JOHN CONNOLLY

Field Quality Investigations

MICHAEL FARRELL

Dealer Support

CHRISTOPHER O’CONNOR

Dealer Support

MELINDA OSTERBUR

Product, Service & Technical Training

ROD ROGERS

Technical Publications

HEIDI SCHULZ

Technical Publications

TIMOTHY TOOMBS

Dealer Support

TechTalk^® is published by Nissan North America, Inc. TCS, Technical Publications. This issue magazine is published to promote information sharing as an informal technical aid for dealership technicians. Nissan/Infiniti names, logos, product names, feature names, and slogans are trademarks owned by or licensed to Nissan Motor Co. Ltd., and/or its North American subsidiaries. Other trademarks and trade names are those of their respective owners.