Do battle with my ignorance regarding electronic car transmissions

I have read the wikis on different types of car transmissions aside from the usual manual and automatic, and I am still none the wiser about the types of “in between” transmissions.

As I understand, there are 2 distinct types of this thing in common usage.

  • Electronic Manual/Clutchless manual transmission. Essentially the same as a manual but moves via electronics.

  • Discrete automatic/Tiptronic transmission. The same as an automatic except the dirver has control over which gear is selected.

My questions:

  1. What commonly seen car types have each kind? Because each manufacturer uses different names for their techs, I can’t figure it out. I understand luxury European sports coupes often have the first type, while “sporty” versions of dometic/Japanese compacts will often have the latter. Is this generalization correct?

  2. What are the pros and cons of each type? Is the tiptronic type transmission any real improvement over the usual automatic transmission? I have some experience driving a Tiptronic equiped MB Gelandwagen, but I never actually used the tiptronic function, and I’m not sure if it really serves any useful purpose on that vehicle. Are clutchless manuals a great deal more expensive than all other kinds of transmissions? Otherwise, why don’t we see them more often on cheaper cars?

Your plain-English explanations are apprieciated.

There are also continuously variable transmissions that are kind of “out there”. My mom’s saturn has one.

There’s three types of ‘electronic manual’.

The first is a simple ‘clutchless manual’ system, where you still have a shift knob, but no clutch pedal. The clutch is under computer control. This system does not support true ‘automatic’ shifting - you still shift like you would in a normal manual transmission, but you don’t control the clutch.

The second is the ‘automated manual’, used most famously by Ferrari. Here, you have a manual gearbox that is entirely under computer control. It can act as an ‘automatic’ by sensing engine conditions and shifting, or it can give you override control via paddle shifters or a shift knob.

The third is Audi’s dual-clutch DualTronic system. Like the automated manual, it’s also entirely under computer control, with a twist. There are two clutches. The odd gears are driven by one clutch, and the even gears driven by the other. When gears are shifted sequentially, there’s already a clutch ‘on-station’, ready to kick in. This makes shifting incredibly smooth when conditions are right.

The Tiptronics et al are electronic automatic transmissions with driver input to their shift programs. The most important difference between these and the electronic manuals is that they are automatic transmissions with bells on, and have the same disadvantages (planetary gear system, torque converter) that any other automatic has.

As mentioned before, there’s also CVTs. The only car on the road that uses a CVT besides that Saturn that I know of is the Nissan Murano.

You might want to check this site - everything seems very comprehensible.

At the bottom of Groman’s Wikipedia link there’s a long list of new cars that are equipped with CVT. They work very well with hybrid systems - Toyota hybrids use them, as does the Ford Escape.

Alfa Romeo is one of the first MASS PRODUCED proponents of the “clutchless manuals” with their Selespeed system. It can be used as an auto, with paddles on the steering wheel or with a flick up / down of a traditionally located gear stick.

A clutchless manual is one of the best ways to go.

I ahve driven a number of the automatic with manual override styles - to me they are a waste of space, and I always just end up leaving the car in auto drive.

By using a manual you get more power at the wheels (automatics typically drain up to 10% of engine power in the gearbox) the resulting greater fuel efficiency.

If you know how to drive them properly manuals also typically give you better / safer handling, particularly in hilly and / or winding terrain - you have a far greater level of control over what the engine will be doing, and how fast you can go - a real plus when going downhill, or you can prevent gear changes mid corner. In a manual you can also be in the “right” gear for overtaking prior to starting the operation (saving the 1 or 2 seconds it takes for an auto to "kick down) which can make a big difference at the other end.

Thanks for the link Crescend, very informative. It seems that the Alfa Romeo/Ferrari seletronic system gives the best of both worlds, at a lower cost than automatic transmissions. So why, then, are they not popular in North America?

What about the Audi dual clutch system? Is there something precluding it from becoming widespread? Both of the above systems seem far superior to the usual systems around here. Why does anyone drive automatic transmissions anymore?

As an aside, reading up on the Audi system, I have found that two cars that would serve me extremely well, the Audi A2 and the BMW 1 series, are not available at all in Canada. :frowning: Is there some reason European manufacturers don’t like to bring their sporty hatchs and coupes over here?

The problem is actually in the “smoothness” of the shift - although it is a computer controlled clutch it still takes a lot of practise to make the shifts smooth - and few drivers can make it as smooth as an auto. THere is also a very big cultural bias in the US against “sticks”. Then on top of that Alfa Romeo are not widely available in the US.

Alfa Romeo typically acknowledges the Audi system to be the best (although only in private) however, for alfa this is actually mainstream - it is only available on selected Audi models.

Historically, ‘premium’ hatches did not do well in NA. Whenever they got introduced here, the market response was underwhelming.

I dunno. I’d gladly take the A3 with DSG if I could get a hold of one and I could afford it. :cool: