What's with this 8-speed automatic business?!?!
 

This 8-speed automatic in the new LS460 seems like a bit of major overkill. I think it's cool, but here is what I'd rather have.

A completely bulletproof five-speed automatic that is GUARANTEED to last the life of the vehicle.

It seems there are engines out there, with regular maintenance that will get 200k miles easy. I don't know of too many automatic transmissions that will last that long.

I wonder who will be the first manufacturer to offer a lifetime guarantee on an automatic tranny? It seems with the electronics and sealed nature of an auto tranmission, the technology should be available to do this.

soon they will go up to 20 speed

and have to shift 15 times just get to the next traffic light :D :LOL:

I think many automatics fail simply because of lack of maintenance.. sometimes because manufacturers make it difficult to maintain. The usual 30K mile oil change for transmissions is often skipped and since many auto's lack a drain plug it is not surprising. I have run into people that changed engine oil way too often and then ignore lubricant in the automatic for over 100K miles. Gears wear and contaminate the lube.

A lot of gears makes for a nice smooth drive (assuming the shift control system is good) but eventually you have to wonder how many is enough.. or at least what is cost effective.

quik, i don't think these types of trannys will be making it down to the commuter/econo car lines for quite a while.

those are the types of cars that people keep for 200-300K miles.

very few original owners will be keeping their LS470 for 300K miles....

Eight speed does seem like a little much. At that point wouldn't you just go with CVT?

My understanding is that most true CVT systems cannot handle much power. They typically use a belt/chain, and rely on friction between such and some pulleys or whatever to transmit the torque, therefore slippage is possible. Whereas a transmission gear cannot do so (at least without catastrophic failure like in some S2000 diffs.)

I've never driven an auto with more than four gears, but I can certainly understand how an eight-speed auto might appeal to the luxury segment.

as long as it's invisible to the user and it has benefits, i don't think most people will care. Also, it's an automatic so it's not like you have to be switching gears all the time, just turn engine on and punch it! simple enough. I am sure Lexus has tested this and deemed it ready for mass production, especially if it's going to debut on their flagship LS460.

so what is the practical advantage of a 7 or 8 speed transmission over a 5 or 6 speed? is the difference significant enough to justify the cost or are they just splitting hairs for the right to brag about their tranny?

I have seen many Auto trannys go well over 300k miles.. I thought that was common in the Honda world?

The point is, (I think) this tranny will be both a good performer (0-60 est. 5.5sec) and good fuel econ (est mid-20s combined). That's let's say 18/26 (city/hwy) (just a guess by me but Lexus claims "mid-20s combined).

My V6 Passat has just 190 hp (exactly half the hp of a LS460) and weighs a good 700 lbs less and takes 2-3 sec longer to get to 60 mph. But is rated at 18/29 mph (I get around 22 mpg) this is with a 5-speed AT.

I think there is a reason for 8-speeds. Some may be bragging rights, but if 5-speed was able to do any better it'd sure make sense to do the 5-speed.

As far as anything guaranteed for life, I wish. It'd be nice for a luxury maker to stand behind their products longer. Like to say "I know you're paying a premium for this car so we'll cover everything for the first 6-years and 100K miles" (oe whatever). But I know the dealers have to make a living (or a killing) so they need to have people pay to keep old cars running or more likely have a reason to buy a new car with a new car warranty all over again every 3-4 years.

You see all the mad talk about getting "gears" in the S2000. I just got 4.56 in mine and it's a lot smarter on pick-up but high revs on the highway. Now Lexus has 8 gears to play with so they can have smart pick-up in low gears but low revs in high gears.