Whitigir

So as I have searched around, the 3rd gen IS 350 has

AWD, RWD

But

AWD is Camry 6 speeds trans ? and RWD is Direct Shift IS-F 8 Speeds ? I don't get it, really ? Lexus ? Really ? Why ?

Or Am I wrong ? the 6 speeds in the IS is also Direct Shift ?

Whitigir

Alright, the curiosity got to me. I just called my dealer, and they confirmed

The 6 speeds in the AWD = the TRADITIONAL Automatic

The 8 Speeds in the RWD = DCT (Dual Clutch Transmission, or Direct-Shift)

......What ?.....Why Lexus ?........I would love to have the 6 Speeds Direct-Shift.....

The reason why I am looking indepth more = Lexus reliability and their customer service, if anything could have gone wrong....and as If I sacrifice my Clutch and ability to Blip it myself....why can't I have a Direct-Shift in the 6 speed ? Makes no senses to me...whatsoever

Hmmm...Probably due to the no Room to place it at....and Lexus doesn't want to Develop a new 6 speeds DCT just for the same car. Ghost......MONEY TALK!!!!

Now I got it: According to all those Humps and Bumps in the IS 3rd gen Line up....the True Champ is the IS-350-RWD-F-Sport. Because, that was the only one got Directly Developed, and Extensively Tested, Tracked on. The rest of the IS-line up = Just Leisure Options for customers. They will just Option it out there, put on what they can, and void what they can not.

Unfortunately, there is no IS-350-F-Sport around me in 200 miles radius...white/red....

tex2670

Don't you want to post this in the IS 3rd Gen forum?

rominl

iTrader: (4)

lexus 8 speed is NOT dct (dual clutch).

carderoni

I would guess the reason the AWD models get the 6 speed is because the 8 speed, which was built for the IS-F, was not designed with the AWD system in mind. Whether they can resolve this for future model years, I don't know. I'm sure they also left the 8 speed off the IS-250 F-Sport (same with the Adjustable Variable Suspension) to create separation between the two F-Sport models.

fastdak25

far as I nkow the reason for no 8-speed in AWD is no room for the 8 speed tranny and the AWD's transfer case.

JDR76

This is correct.

AdvanSLF

i believe this is correct.. i don't ever recall any mag, column, review, critic, saying anything about the 8speed being dct..i think dct's can shift in 1/1000th of a second.. the 3IS doesn't seem to shift that fast, at least by my experience.

carderoni

It falls under the broad category of electronically controlled automatic transmissions, which are classic automatic transmissions with torque converters that are controlled programmatically or manually rather than strictly mechanics.

hades281

A lot of mis-information in this thread...

A Camry is front wheel drive. It uses a transaxle - totally different gearbox than in any of the Lexus RWD/AWD cars. The only thing the 6-speed IS transmission has in common with the Camry is the number 6 (and they are both made by Aisin).

The 8-speed IS-F transmission is only used in the IS350 RWD and it is not a dual-clutch unit. Personally, I'm quite happy about that - the dual clutch units have their own quirks that to me aren't worth the "performance benefits."

AdvanSLF

What quirks are you referring to?

Whitigir

Isnt Direct Shift the Dual Clutch under different name ? Lexus advertised 8 speeds is the direct shift coming straight off the ISF

TheShaddix

Direct shift is still a single clutch auto transmission whereas a DCT has two clutches and is still a manual automated transmission so there isn't a clutch pedal. Two different things. And it shows too when you drive it.

He's probably talking about dct at slow speeds being quirky and jittery. A friend of mine with a GTR said that too. But that to me is a small price to pay vs. the benefits of instant shifts and downshifts, and we all know that the IS sucks at downshifting (8th to 4th in about 5 seconds...)

And more on topic, i've driven the regular 6 speed IS 250 and I can say that there isn't much difference between the 8 speed and that as far as shift times and overall feel. The standard 6 speed shifts really fast, nothing like the previous gen. So no one should feel like they're missing out on anything here.

rominl

iTrader: (4)

it's a very debatable topic. some say dct can have more computer / electronic issues, and at the same time dct is heavier than single clutch system for example as well.

the similar kind of debate went on for long even for cars like the lfa

totally different things. direct shift is still automatic transmission, no clutch, and if i am correct, it's engaged when you are in sports mode where the torque converter basically locks up for a faster more precise shift

dct is actual real manual transmission with clutches, except there is no clutch pedal because the computer does all the shifting process for you, thus the faster speed

currently lexus has no dct in their whole lineup at all. the lfa is single clutch

05RollaXRS

Direct shift means the lockup torque converter is locked from 2- 8 gears in manual mode. So the slippage from gear to gear does not happen since the torque converter is locked (torque converter is what really gives automatics the "smooth" feel as it glides from gear to gear)..

This lockup gives the shift a crisp feel with a brief pause between the shifts making it feel like a manual transmission.

Only the Lexus LFA has an automated (robotized) manual transmission in the Lexus line up.