Did you know about temporary shift range?

[Flytvr]

1 hour ago, lotusdave said:

umm, wanna overtake and pre select the right gear? Flick the left hand paddle. Why would you want to press a tiny little button by your knee?

or flick the big gear lever over and go manual....

mine is fine in traffic. I suspect that in comparison to a rolls Royce its rubbish, but compared to a manual Elise its as smooth as silk.

Button by knee? Are you talking about the 'shift lock' button. I thought that was for breakdowns?

[Big Rat]

Any one seen this before-not the whole article just the gearbox section.

Big Rat

The IS F 5.0-liter V8 engine is mated to the world’s first eight-Speed Sport Direct-Shift automatic transmission. This new transmission blends the performance characteristics of an automated manual-type transmission with the smoothness and refinement of a planetary-type automatic transmission. As a result, the driver can choose between ultra-quick manual shifts for performance driving, and smooth automatic shifts when convenience is the top priority. The driver can shift manually using either the console shift or steering-wheel-mounted paddle shifters.

The eight-speed transmission is approximately the same length and width as the six-speed transmission used in other rear-wheel drive Lexus models. The transmission has a die-cast aluminum case and some aluminum internal parts, which contributes to weight reduction. Using eight speeds allows gear ratios that maximize torque up to the tire-grip limitations in the lower ranges while optimizing efficiency.
 

Driving enthusiasts will appreciate the transmission’s Manual mode (M), which will hold each gear to the 6,800-RPM redline. A pair of unique paddles located within a fingertip’s reach behind the steering wheel enables the driver to make ultra-fast up-shift gear changes. Paddle-shifting operation is allowed in either D or M modes, but shifts are quicker and more direct in M mode. At higher engine speeds, downshifts are accompanied by automated and precise throttle blips to match engine rpm to vehicle speed.

In addition, a Sport mode switch on the dashboard allows the driver to select from among Normal, Sport and Snow driving modes. In Sport mode, the VDIM system allows higher dynamic thresholds before intervening, alters steering assist to increase steering weight, and throttle response is sharpened. With the transmission in D mode, gears are held longer in response to throttle input.

Versatile Drive Mode

When the driver selects Drive mode (D) using the console shifter, the eight-speed transmission provides quick shifts that are smooth and befitting a Lexus. At the same time, D mode offers plenty of versatility with full torque-converter lockup in 6th through 8th gears to optimize fuel efficiency. A flex-lockup clutch operates in 4th and 5th gears, continuously controlling lockup-clutch slippage to enhance fuel efficiency.

Until the engine reaches operating temperature, and when the VDIM system detects slippery road conditions, the transmission will automatically select 2nd gear start. Once the engine reaches operating temperature, or VDIM detects better road conditions, the transmission allows 1st gear start.
 

From D mode, the driver can select M mode by moving the console shifter into the M slot, or can gain temporary sequential operation by keeping the console shifter in D and operating the steering wheel paddle shifters. The latter is useful for situations where engine braking is desired, such as driving through a hilly area.

Paddle shifting while in D mode, however, is not the same as in M mode. If the vehicle is stopped, or if the vehicle is at a constant speed for a certain period of time, the transmission will change back to normal D operation. In addition, the driver can switch immediately into normal D operation by holding the upshift paddle (+) for one second.

The transmission uses flex-lockup control and deceleration control when decelerating while in D mode, using as many gears as possible and extending the fuel cutout for maximum efficiency. AI-SHIFT (Artificial Intelligence-SHIFT) complements the driver’s Sport switch selection by automatically adapting the shifting based on road conditions and driver input. The new transmission is also highly responsive to uphill/downhill driving, always selecting the best gear for power or engine braking. Because the IS F is a Lexus, the intuitive powertrain control optimally smoothes out off-the-line response.

Sporty Manual Mode

Manual mode (M) goes beyond simply allowing manual gear selection by changing the transmission’s operational behavior to facilitate performance driving. In M mode, the driver will experience the feel of a manual transmission. Specifically, one will feel immediate g-force during acceleration and deceleration. In addition, the transmission uses downshift blipping control to match engine speed for high-rpm downshifts.
 

The driver selects M mode using the console shifter, which then allows upshifts by pushing forward (+) and downshifts by pulling rearward (-). With the console shifter in M, the driver can also use the paddle shifters mounted behind the steering wheel.

In 1st gear, the torque converter operates to provide torque multiplication for consistent launches from a standing start. The torque converter is locked continuously in 2nd through 8th gears to provide a direct connection between engine and transmission for the fastest shifts and most direct driving experience.

In M mode, gears will be held until the driver up- or down-shifts. Two exceptions are if vehicle speed falls too low for the selected gear, then the transmission will downshift automatically; and if the transmission fluid or engine coolants exceed limits, then the transmission will revert to automatic operation to prevent damage.

Shifts In 0.1 Second And Downshift Throttle Blipping

New hydraulic-control technology allows the IS F 8-Speed Sport Direct Shift transmission to perform on par with manual transmissions without sacrificing the smoothness of a torque-converter automatic. In M mode, upshifts are executed in just one-tenth of a second, six times faster than manual shifts in the V6-powered IS models.

The transmission-control system uses high-flow linear control valves for engaging and disengaging the clutches. The resulting simultaneous release and engagement of the shifting clutches provides fast shifts while diminishing gearshift shock. The solenoids allow direct control of the hydraulic pressure applied to the shifting clutches, along with centrifugal fluid pressure canceling mechanisms, enabling finer control than conventional clutch-control systems. In addition to a conventional input-shaft speed sensor, the intermediate members of the gear train use a speed sensor to allow finer control of gear changes.

Driving enthusiasts pride themselves on the ability to execute a perfect manual-transmission downshift, which requires "blipping" the throttle while the clutch is disengaged to match the engine speed for the lower gear. The IS F transmission executes perfect downshifts in a similar way but with the consistency most drivers cannot match with a manual transmission.
 

When a downshift instruction is received, the transmission control system quickly opens the electronic throttle, instantaneously increasing engine speed (blipping) to match the engine speed after the gear change. Simultaneously, the system completes the gear change by smoothly and quickly engaging the shift clutch. The downshift, with throttle blipping, occurs in just 0.2-second.

To enhance performance and durability, a breather system separates air bubbles from the transmission fluid during performance driving. The transmission is also equipped with an air-to-liquid automatic transmission fluid (ATF) cooler to help ensure optimal transmission performance even during track driving. There is a transmission fluid temperature warning-light in the instrument panel.

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[Chuckie478]

On 17/01/2017 at 4:52 PM, Flytvr said:

Before running off to Google (or reading the manual), do you all know about the gearbox functionality and 'temporary shift range'.

I had no idea!

I knew it existed, tried it on the test drive before I bought it after the Jaguar XFR I test drove a few weeks before did something similar.  Had no idea that's what it was called though.