Why do 6-speed manuals exist?

[02SE]

Originally Posted By: Virtus_Probi
My old man learned to drive a manual on the Model T he bought from his brother when he was 14 and thought that anybody who would buy a stick after automatics were invented was a moron!!
;^)


Lost of people view cars as nothing more than an appliance. Increasingly, there are those that simply don't know how to drive a manual transmission, and have no interest in learning. Then there are those for whom having to change gears manually, would interfere with tweeting, texting, and posting non-stop selfies to their BFF..

 

[barryh]

A 6 speed manual is a real refinement and economy benefit on my Mercedes C180K as 6th is geared at 31 MPH/1000RPM. My previous C class car was only 25 MPH/1000RPM.

While the a cruising ratio would be nice I don't think I'd like 6 gears on my motorcycle mainly because knowing what gear you are in at any point in time is a memory exercise and my old brain would struggle with counting the extra ratio. I have enough trouble knowing where I am with 5.

 

[JHZR2]

Its all about keeping the power band in play for as effective and efficient a drive as possible. In many conditions, an AT with some logic and mapping could do as well if not better, but not always.

My father had a car in the early 80s that had some sort of dual range MT for economy and power. IMO something like that may be beneficial.

These days vendors gear a lot of vehicles kind of silly. That said, its true with ATs as well, with Toyota as an especially bad culprit of an overly jumpy and barely useful 1st get in their AT (matrix and highlander I have first hand experience). A smartly geared MT system, with a usable 1st gear, a second gear that can be operated from a stop or near stop without a stall or excessive throttle, and then an OD or two works pretty well. I did >>100k of DY, NYC and Philly traffic in my 91 BMW ant it never struck me as fatiguing or annoying because it was geared well. Ive also driven some MTs that you can barely put it into first rolling through an EZpass toll booth at 5 mph, yet put it into 2nd and it practically wants to stall. Not that it cant be overcome, but its just stupid. A well geared MT is ideal for control, economy and lifecycle cost.

 

[demarpaint]

Originally Posted By: heynow
Originally Posted By: veryHeavy
Okay. WHY do people want 6 speeds instead of 5? In my driving I saw no advantage to having to shift an extra gear.
Quote:
Why have more than a 3 speed right? I mean 3 speeds are enough?

Clearly you did Not Understand my post. 3-speeds did not have the ultra-high gear ratio as the 5-speed, so there was a real difference upgrading to 5 (fuel savings).

But these new 6-speeds have the same top-end gear ratio, so nothing's changed. No improvement in fuel economy.




Assume that the theoretical three speed DOES have the same gear ratio spread and same top gear ratio as your five speed. Basically your five speed minus second and fourth gears. How do you think it would be to drive?


Not as good as the 5 speed, especially on hilly terrain, or for many situations where a downshift to pass someone is needed.

Having said that there is a point where too many gears is too much. The engine needs adequate torque to take advantage of some of the higher gears. Searching and constant up and downshifting as well as lugging an engine can be very annoying. Case in point I have driven newer Grand Cherokees with the 8 speed AT and found it quite good. OTOH I drove a 2016 Cherokee with the 9 speed and hated it.

 

[bunnspecial]

The only M/T I currently own is a 4-speed, although the top ratio is 1:1(optional electric O/D, which I don't have) so it can be thought of similarly to a traditional 5 speed in terms of ratios.

On that particular box, there is-to me-an uncomfortable jump in ratios between 2nd and 3rd. For "spirited" driving, for example, I often find that I'm lugging the engine and just lack any real ooomph to pull out of a corner when I'm in 3rd gear. At the same time, however, 2nd is WAY too low for any reasonable driving in that situation. To me, having a ratio somewhere between those two would be great. On popular upgrade for my car is to install a Datsun 5 speed, which of course doesn't give an additional ratios vs. the O/D box, but does at least put 2nd and 3rd in a relatively more useable position.

As said, having more ratios available doesn't mean you have to USE all of them. In fact, in some vehicles GM actively discourages it by forcing a shift from 1-4 under certain driving conditions.

 

[Ducman]

It depends upon the application with the available gearing in the transmission and final drive.
6 speeds are awesome when paired with a V8 that is in street tune(400-480 hp) with lots of low down torque, or even a good turbo 6(Australian) works nearly as well.
That is with 5th and 6th being overdrives and 6th gear being "the economy gear".

The key is having enough power and torque that's accessible enough to be able to drive the vehicle as a 3 speed when getting around on a casual basis.
For example in an uphill take off at the lights, a 1-3-5 shift sequence works great.
For a flat ground or down hill take off, a 2-4-6 shift sequence is just as good.
Obviously, when using the engine potential to its fullest one can select any ratio for a given situation to keep the engine in an appropriate part of the rev range.

IMO, given the above scenario the typical Front wheel drive 4 banger is exempt from having all that much practical benefit other than giving one the right gearing option in greatly varying road conditions. I should imagine on flatter terrain the 6 speed would not be so beneficial in this case.

 

[Ducman]

Originally Posted By: heynow
Originally Posted By: veryHeavy
Okay. WHY do people want 6 speeds instead of 5? In my driving I saw no advantage to having to shift an extra gear.
Quote:
Why have more than a 3 speed right? I mean 3 speeds are enough?

Clearly you did Not Understand my post. 3-speeds did not have the ultra-high gear ratio as the 5-speed, so there was a real difference upgrading to 5 (fuel savings).

But these new 6-speeds have the same top-end gear ratio, so nothing's changed. No improvement in fuel economy.




Assume that the theoretical three speed DOES have the same gear ratio spread and same top gear ratio as your five speed. Basically your five speed minus second and fourth gears. How do you think it would be to drive?


I would assume the 5 speed is an overdrive.
In this case, the theoretical 3 speed would be an absolute dog.

 

[expat]

My Triumph Spitfire has electric overdrive that works on 3rd and 4th gears.

O/D 3RD is between 3rd and 4th gear, O/D 4th is like a 5th (O/D) gear.

On a hill I may change to O/D 3rd when normal 3rd would be a bit low.

I would not use all the gears in sequence.

 

[Burt]

I had a 6-speed manual. Felt like I was 'rowing' the car rather than shifting.

 

[A_Harman]

Originally Posted By: vintageant
Why do road bikes have 15 speed? Discuss.


Human's are like diesel engines in that they have a narrow rev range. I'm pretty much trained to run 80 rpm, then shift gears to match effort and road speed.

 

[Michael_P]

Hey, how exactly is a rainbow made?
How exactly does the sun set?
How exactly does the posi-trac rear end on a Plymouth work?
It just does. It just does.

Joe Dirt (dad)

 

[spasm3]

Originally Posted By: DuckRyder
Something seems familiar here.


+1

 

[double vanos]

There's nothing more enjoyable than driving a car with a good revving engine and a slick shifting 6 speed with the ratios stacked close together.
Anybody remember when you could buy your Super Sport Malibu with either the close ratio 4 speed or the wide ratio 4 speed? The close ratio boxes were always the most fun....

 

[Merkava_4]

Wow! It's taking me forever to scroll to the end of this thread.

 

[A_Harman]

Originally Posted By: ls1mike
Originally Posted By: KitaCam
I'm with Sup....preferring the 5-speed over the 6-speed...it gives me greater rpm range in each gear for less shifting around town...

Sure in a 150hp 16 second Camry that works fine.

But having an extra overdrive in the Trans Am makes all the difference in the world. I use the first 4 gears around town, 5th gear when going under 60.
Your car does not have the torque of say an LS1. In 6th gear going 45-50 up a 7 percent grade hill I mash the go pedal and don't have to shift it just does what it has to. No lugging, no crying, just sweet LS1 action...

Yep, I've always loved the pairing of the LS1/T56 in my Camaro. It has been such a well-matched powertrain, I've never felt a really strong urge to change anything. Of course more power would be nice, but the gear ratios may have to be refigured. Top speed in the 4th-Gen F-body is achieved in 5th gear. I have gotten the Camaro up to 155 mph on the race track (Daytona) a few times. This put the engine at 5200 rpm, which is where is makes peak power in stock configuration. Top speed in 6th gear I have heard is 138 mph, but I've never had a chance to check that out for myself. (All this with the 3.42 gear.) In street driving, I shift into 6th at 64 mph, which puts the engine at 1400 rpm, and it will putt up 6-7% grades alright. A large displacement slow-turning engine will get just as good fuel economy as a small displacement fast-turning engine.

 

[Bud]

Originally Posted By: rideahorse
I don't know why automatics exist. Just for people that don't have the ability to drive.


Dumb very judgemental statement. I learned how to drive on a manual. Owned many cars that were manual and still have an old MG. I will be 70 this year and have no desire for a new car without automatic. I expect there are many that feel just like I do. Has absolutely nothing to do with ability to drive.

 

[bunnspecial]

Originally Posted By: expat
My Triumph Spitfire has electric overdrive that works on 3rd and 4th gears.

O/D 3RD is between 3rd and 4th gear, O/D 4th is like a 5th (O/D) gear.

On a hill I may change to O/D 3rd when normal 3rd would be a bit low.

I would not use all the gears in sequence.


I know a lot of folks who drive their O/D MGs similarly, except that on an MGB transmission 3rd O/D is roughly the same as 4th no o/d(1:1). For around the town driving, they find cruising in 3rd and kicking it in and out of O/D a lot more convenient than shifting between 3rd and 4th. I'm still kicking myself for not spending the money for an O/D when I changed mine(granted my non-OD was free)-the thought of 70mph at 2800rpms is very appealing

.

 

[ls1mike]

Originally Posted By: Burt
I had a 6-speed manual. Felt like I was 'rowing' the car rather than shifting.

As it should be.

 

[Jarlaxle]

Originally Posted By: heynow
Originally Posted By: veryHeavy
Okay. WHY do people want 6 speeds instead of 5? In my driving I saw no advantage to having to shift an extra gear.
Quote:
Why have more than a 3 speed right? I mean 3 speeds are enough?

Clearly you did Not Understand my post. 3-speeds did not have the ultra-high gear ratio as the 5-speed, so there was a real difference upgrading to 5 (fuel savings).

But these new 6-speeds have the same top-end gear ratio, so nothing's changed. No improvement in fuel economy.


Assume that the theoretical three speed DOES have the same gear ratio spread and same top gear ratio as your five speed. Basically your five speed minus second and fourth gears. How do you think it would be to drive?


Just fine, as long as it was behind the right engine!

 

[Jarlaxle]

Originally Posted By: double vanos
There's nothing more enjoyable than driving a car with a good revving engine and a slick shifting 6 speed with the ratios stacked close together.
Anybody remember when you could buy your Super Sport Malibu with either the close ratio 4 speed or the wide ratio 4 speed? The close ratio boxes were always the most fun....


Except when starting on a hill with that 2.20 low gear!

I like what Rick Ehrenberg did when he built his road-race Valiant: he used a 4-speed (in a near-unobtanium Direct Connection aluminum case), but with 6-cylinder guts for the lower (3.09, compared to 2.65 or 2.44) first gear, and ran tall (2.94) axle gears.