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Discussion Starter #1
Okay. Most of us have had some time to go beyond our first impressions (where typically everything is great about this car) to form opinions based on everyday, longer term use. The subject here is the 8 speed tranny. After putting some 2,500 miles on my ISF I would have to say that 8 gears is 2 gears too many. It seems like the car is always searching for the right gear to be in when I get lazy and place it in "D". There are just too many upshifts and downshifts. I haven't logged the data for this impression to be sure but I think the rpm's only drop some 300-400 when going from gear to gear. There's really not all that much difference between 4th and 7th in terms of rpm's. When in "D" and with the computer display set to show which gear I'm in, it seems the car gets into 8th gear at around 40mph when not accelerating quickly. Were I in manual mode I'd be in 3rd or 4th at 40mph.

Also on the subject of the transmission, I guess I'd have to say that given a choice I'd prefer this car to give me a 6 speed true manual tranny over the 8 speed auto manual. I understand that it shifts much faster than I could manually with a foot clutch but it also lowers the overall driver involvement. Tapping the steering wheel pedals just isn't quite the same as slamming down the clutch and throwing the car into gear. I know, how 20th century of me.

I guess that's my only negative thoughts thus far about the car. Not really complaints so much as a preferences.
 

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I can understand what you feel about the "Automatic", but remember, 7th and 8th are an overdrive gears. They do drop more than a few hundred RPM's.
 

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Just use the sport mode in manual and have fun..... When you feel lazy or in traffic the auto mode is great in city driving. Stick shift in formula racing went by the wayside in about 1991. Remember, you do have the worlds first 8 speed tranny with direct hookup IN GEARS 2-8. ENJOY! WHILE OTHERS ARE ENVIOUS.
 

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Couldn't agree more, old$parts. Tranny is truly brilliant. Sport mode gives you almost a different car, entirely. That's where the fun is, in my opinion.

Rushnut
Next speeding ticket court appearance: 7/8/08, Long Beach Superior Ct. (CA)
 

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8 gears are great especially when just cruising on the highway. It really yields the best gas mileage. But I do have to agree that when putting the car in just "D" mode (or even with the sport button on), 8 gears is a bit much for the car to decide what gear to be in. If I am cruising in 8th, then floor it, it takes a moment for the car to kick me down to the gear I really should be in. It's a bit frustrating. But if in Manual and in Sport mode, this car is great! Very responsive, quick... but I'm making the decisions.
 

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8 gears are great especially when just cruising on the highway. It really yields the best gas mileage. But I do have to agree that when putting the car in just "D" mode (or even with the sport button on), 8 gears is a bit much for the car to decide what gear to be in. If I am cruising in 8th, then floor it, it takes a moment for the car to kick me down to the gear I really should be in. It's a bit frustrating. But if in Manual and in Sport mode, this car is great! Very responsive, quick... but I'm making the decisions.
IMO....It's really no different in "D" than it would be driving a manual. If you want to immediately downshift to gears 6 or even 5, it's just a tap on the left shift paddle for instant response. With a 6 speed manual car you would have to downshift for fast acceleration and it would be even slower in response times by shifting manually! That's why Lexus advertises the World first and fastest shifting production car made....It's really bulletproof technology!!!
 

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IMO....It's really no different in "D" than it would be driving a manual. If you want to immediately downshift to gears 6 or even 5, it's just a tap on the left shift paddle for instant response. With a 6 speed manual car you would have to downshift for fast acceleration and it would be even slower in response times by shifting manually! That's why Lexus advertises the World first and fastest shifting production car made....It's really bulletproof technology!!!
When I made my comment, I'm talking about just leaving it completely in D. I realize you can still downshift in D manually, but what if you were going 65 and needed to cut over and you pressed your accelerator. It takes time to go from 8th gear to whatever gear that would be optimal. In the IS350, if you kept it in D, it responded pretty well. From 6th to 4th in the IS350 it happens pretty quick, from 8th to 4th in the IS350 takes a while. Yes I realize I can downshift, but I was talking about having just the automatic transmission logic work by itself.
 

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If you were driving a car with a manual tranny you would still not have any real acceleration to get into another lane quickly if it was in 6th gear.
(No car is going to have a tremendous amount of torque in high gear when you want to suddenly switch lanes.)
You would probably downshift to get more torque and that does take time also. I just can't invision the process taking any longer with the Lexus downshifting in the D mode. There are just too many positive points about the ISF tranny that reign over a manual. Wait and watch who the next big auto makers are that start introducing the 8 speed tranny in the near future.
 

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I wasn't talking about comparing manual vs the 8 speed. I was talking about the responsiveness of the car from cruising state at the top gear to the optimal gear for that acceleration. If I was driving a manual or even the IS-F's transmission in manual, I would downshift before I cut over and pass. I'm just talking about the actual time it takes for the IS-F's 8 speed to go from 8th to 4th. It will take a while because it steps down through the gears. 8th and 7th are great for saving gas! Do you have an IS-F?
 

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Oh Yeah! Mercury Metallic.....I did some driving today. I use the sport mode a lot and when I press the accelerator it jumps down sometimes 3 or 4 gears almost instantaneously. I find that even in drive mode, if you press down slightly on the accelerator it will begin to downshift, however with spirited driving it works fine for me. The slight time allowed to downshift is minimal, accurate and positive every time with the proper blips for a smooth transition compared to attempting the same shifting type maneuver with a manual and hitting the rpms in perfect resonance with the cars meshing of speed and torque. There aren't any real 8 speed manual transmissions available to even test of how the same type of shifting pattern would effect the feel of the 8 to 4 downshift ratio.
Lexus is the pioneer and reigns supreme in this department!

Don't misunderstand me, sticks are fun if that's youy\r thing! I just sold a Shelby GT 500 with 500 horsepower. It just doesn't compare to the ISF in any category!!!!

Old$parts
 

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If you're at a track, depending on the length and technicality, you're always going to stay within the first 4 gears. 5-8 is literally not used unless you leave it parked in D mode the whole time.
 

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Discussion Starter #12 (Edited)
I find that even in drive mode, if you press down slightly on the accelerator it will begin to downshift, however with spirited driving it works fine for me.
Old$parts
I think this was my original point. Pressing down even slightly on the accelerator causes a gear change. Why? Because the ratios are too close together. Why? Because it has 8 gears instead of 6. This engine has more than enough torque to efficiently pull the car in any gear at any speed. The additional 2 gears just seem superfluous.

Perhaps it's the the "World's First 8 Speed Tranny" because others have decided that 6 Speeds more than suffice.
 

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Merceds Benz and BMW now have a 7 speed in some of their vehicles. Like I stated before, 7th and 8th gear are "cruise gears". Those gears help out with the Fuel Efficency when you set the Cruise at 80 mph and are under 2,000 RPM's...
 

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8 speed transmissions are here to stay!

I think this was my original point. Pressing down even slightly on the accelerator causes a gear change. Why? Because the ratios are too close together. Why? Because it has 8 gears instead of 6. This engine has more than enough torque to efficiently pull the car in any gear at any speed. The additional 2 gears just seem superfluous.

Perhaps the the "World's First 8 Speed Tranny" because others have decided that 6 Speeds more than suffice.
Answer to your comments:

Wrong! Others have decided to join the band wagon, in this case LEXUS is the leader of the bandwagon...!:) .


Perhaps you might want to check out whats happening with the BMW, Audi and Mercedes cars comming out! The 8 speed is here to stay and Lexus is the leader.
Check this info quoted from [Autoblog]

Auto News
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Audi and BMW to utilize 8-speed gearboxes to take on Lexus
Posted May 12th 2008 2:57PM by Michael Harley
Filed under: Car Buying, Sedans/Saloons, SUVs, Tech, Audi, BMW, Lexus, Mercedes-Benz


As we reported last month, it appears BMW and Audi, following the lead of Lexus, will begin to offer eight-speed automatic transmissions in their flagship models. Sources are now saying the transmission will be supplied by ZF Friedrichshafen, a familiar German supplier to both marques. Although we don't know all of the specifics, Audi is expected to debut the new slushbox in the range-topping A8 sedan, Q7 SUV, and their future A7 premium model. BMW will likely debut the new gearbox in their premium 7-Series sedan and the X6 Sport Activity Vehicle, according to company sources.

The current Audi A8 and BMW 7-Series both use six-speed automatics. The Mercedes-Benz S-Class utilizes a seven-speed automatic of their own design, while Lexus debuted their eight-speed transmission in the LS 460. Increasing the number of forward gears offers advantages in smoothness, acceleration, and improves fuel efficiency. Lower fuel consumption equates to reduced emissions, helping the powerful models meet increasingly stringent air quality standards in Europe and the United States.


When BMW released the redesigned 7-series back in 2001, they were the first to offer a six-speed automatic transmission. Two years later, Mercedes upped the ante by throwing an additional cog into the mix, equipping their new S-class with a seven-speed auto. Now that Lexus is offering an eight-speed slush box in their waftastic LS460, BMW has vowed not be left behind in the ratio wars and plans to bring an nine- eight-speed transmission to market by the end of the decade.

The next 7-series will be due for a substantial redesign by 2009 or 2010, so that's when industry analysts expect the eight-speed box to find its way into BMW's luxury sedan. The engineering haus, ZF Friedrichsafen, has been tapped to create the new automatic and has plenty of experience increasing fuel economy, while decreasing build costs, on the current model's six-speed automatic.

When will this cog-swapping numbers race end? We're not entirely sure, but as soon as manufacturers start cresting the double digits, we doubt anyone will even be paying attention.

Source: Automotive News – Sub. Req.]
 

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More interesting info:

ZF Turns The Tables And Follows Lexus With An 8 Speed Transmission
Agent009 submitted on 05/03/2007 Official AutoSpies Timestamp: 10:33 AM
from: www.autospies.com
[20] user comments | category: Misc News

Print this Page | Digg It | del.icio.us
ZF Turns The Tables And Follows Lexus With An 8 Speed Transmission
ZF has designed a new automatic transmission generation for passenger cars: With the automatic 8-speed transmission the chassis and driveline specialist succeeds once more in combining seemingly contradictory goals. The automatic ZF 8-speed transmission allows for additional fuel savings of approximately six percent compared with the already optimized automatic 6-speed transmission of the second generation. This is achieved above all by a completely new transmission concept. At the same time, the automatic 8-speed transmission transmits more power in comparison to the previous model, but still gets by with the same installation space and does not require more components. Last week, the new 8-speed transmission was presented for the first time at the 28th International Vienna Motor Symposium.

“Our main development target was to find a transmission concept which allows for significant additional fuel consumption reduction and thus offers tangible added value to our customers and drivers without making any compromises in terms of performance”, explains Dr. Michael Paul, ZF Executive Vice President, Technology and Group Executive of the Car Driveline Technology division. “The number of gears was not given top priority.”

Fuel consumption savings as development target

The new, more powerful ZF multi-ratio automatic transmission allows for consumption savings of six percent. This means that the excellent consumption values of the second-generation automatic ZF 6-speed transmission which entered volume production only in 2006 have been further improved considerably. To make it clear: Compared to an automatic 5-speed transmission which is still widely used today the consumption reduction amounts to approx. 14 %.

old$parts
 

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Discussion Starter #16
My assumption all along was that a reason for the 8 speed transmission had to be some advantage in regards to fuel consumption. At 16 mpg in the city, a 6% savings in fuel efficiency would put it at 15 mpg. Not exactly Earth shattering.

I am pleased to read that there also seems to be some advantge in power delivery. Assuming this is a measurable advantage then that alone is good enough reason for the 8 speed auto.

I appreciate all the good info. Given the choice, I'd still rather throw a stick into gear myself, but at least I understand Lexus' thinking now.
 

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COOL ! I understand where you're coming from.

I guess that my enthusiasm for the ISF is evident.
I just got tired of shifting my Shelby GT500 in city driving.
I now have several choices on how I want to shift in the IFS....
Perhaps old age is kicking in.

old$parts
 

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Like you, I like to be able to shift when I want to (using the paddles in manual mode) and not have to think about it when tied up in traffic. I drive about 70 miles on the beltway every work day, at times in stop and go traffic. At those times I just move the shifter to automatic and let the transmission do the thinking for me. At other times I like to put it into Sport Mode and disengage the traction control and just go like a "bat-out of ----"

I too am getting old, I guess, but I have had fast cars all of my life and don't intend to change now. My 38 year old son and I are headed for Atlanta in a few weeks for the Lexus Driving Academy. BTW I will be 70 in New Years Day.
 

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Congratulations on your upcoming 70th birthday!

BTW, I'm 66 an enjoying everyday from sun-up, in-between, sun-down and into the late night hours. I feel like no more than 40 and won't settle for anything less than fast. Oh, I forgot to mention that I also have a Corvette for changing up the scene once and awhile. I just might have to think about trading the Vette soon for a CTS-V [Automatic]. The desire for this beast is starting to wear on me.

old$parts
 

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"I just might have to think about trading the Vette soon for a CTS-V [Automatic]. The desire for this beast is starting to wear on me" ---- OLD$PARTS

I suggest you wait for the 2009/2010 model because Cadillac insists on being "THE FASTES SEDAN" in the market with a 550hp supercharged engine,maybe 3.2/3.3 sec to 60 mph!!!
 
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