History of the A650E Transmissionby Rob Wagner
The Toyota A650E five-speed automatic transmission matched engines in a wide range of Lexus luxury cars from 1998 to 2005. The five-speed was somewhat overshadowed by the more popular six-speed automatics and often sparked complaints from Lexus buyers, who could only order their cars with the A650E and not a five-speed manual. Yet the A650 provided smooth shifting and helped increase fuel efficiency.
The A650E was a five-speed electronic control transmission that was virtually identical to its hydraulic automatic transmission siblings, but used an electronic control unit, electronic sensors and numerous electronic parts to shift gears. The sensors monitored the Lexus' speed, throttle opening and gear selection. The sensors then sent the information to the electronic control unit, which in turn operated the clutch, shift points and torque converter lock-up. The driver could manually set the shift pattern to "Normal" or "Power." This allowed the electronic control unit to properly select a shift point. For example, when the transmission upshifted to third gear with the throttle at 50 percent, the speed was 37 mph in "Normal" mode and 47 mph in the "Power" mode.
Lexus used the A650E in the mid-priced, mid-size luxury sports sedans and executive 1998 to 2005 Lexus GS 300, 1998 to 2000 GS 400 and the 2001 to 2005 GS 430 models. It was also available in the entry-level 2001-2005 IS 300 and the high-end, full-size 1998 to 2000 LS 400 and 2001-2003 LS 430. The 1998 to 2005 RS 200 and the 2001 to 2005 personal luxury coupe SC 430 also received the A650E five-speed automatic.
Lexus IS, LS and SC Engines
The A650E was most commonly found in the Lexus IS 300 models. The transmission matched a 215-horsepower, 3-liter in-line six-cylinder engine wielding 218 foot-pounds of torque. The IS 300's performance was excellent with the automatic, achieving zero to 60 mph in less than seven seconds. Yet, potential buyers noted that while the A650E was fine, the IS 300 lacked a manual transmission. It wasn't until 2002 that Lexus offered the choice of a five-speed automatic or a five-speed manual; however, the IS 300 SportCross wagon only received the A650E. The A650E also demonstrated that it could handle the additional stress of more horsepower in the LS 430, which was equipped with the 290-horsepower, 4.3-liter V-8, as well as in the SC 400, which was equipped with a 260-horsepower, 4-liter V-8.
The A650E five-speed automatic had a 3.357-to-1 first gear ratio, a 2.180-to-1 second gear ratio, a 1.424-to-1 third gear ratio, a 1.00-to-1 direct fourth gear ratio and a 0.753-to-1fifth gear ratio. The reverse gear ratio was 3.266-to-1.
The Toyota A45DE four-speed automatic derived from the GS 300- and LS 400-installed A650E automatic transmission. In the IS 200 models, it featured a redesigned electronic control unit to maximize fuel efficiency and give smoother shifting. The IS 200 used the ECT-iE technology -- or electronic control unit -- to determine the shift mode depending on driving conditions. It also employed the torque converter lock-up if the Lexus was cruising and not power-driving. The A45DE, like the A650E, provided conventional automatic mode or a manual mode to determine shift points.
Rob Wagner is a journalist with over 35 years experience reporting and editing for newspapers and magazines. His experience ranges from legal affairs reporting to covering the Middle East. He served stints as a newspaper and magazine editor in Saudi Arabia and the United Arab Emirates. Wagner attended California State University, Los Angeles, and has a degree in journalism.