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Hom3r
24-02-2007, 22:44
I'm driving to Belguim tomorrow, and we've got a Zafira hire car which has a 6 speed gearbox.

What is the 6th gear for?

Xaccers
24-02-2007, 22:46
I'm driving to Belguim tomorrow, and we've got a Zafira hire car which has a 6 speed gearbox.

What is the 6th gear for?


For keeping the engine revs low while you're travelling at speed.

Wicked_and_Crazy
24-02-2007, 22:47
ermmm do you not understand how to drive!!

when the engine is reving high enough in fifth you can move up to sixth. You would use it the same as you would fifth in a standard car or forth in a 15 yr + old car

must admit i do struggle when i have to go back to 5 gears.

Hom3r
24-02-2007, 22:49
So its an extra 5th gear?

---------- Post added at 22:49 ---------- Previous post was at 22:48 ----------

I've been driving for eighteen year and wonder why there was a 6th gear.

My car has a 5th gear and this keeps the revs low.

Wicked_and_Crazy
24-02-2007, 22:50
So its an extra 5th gear?

---------- Post added at 22:49 ---------- Previous post was at 22:48 ----------

I've been driving for eighteen year and wonder why there was a 6th gear.

My car has a 5th gear and this keeps the revs low.

no, its higher than fifth, the high to low ratios have just been divided into 6 rather than 5

SMG
24-02-2007, 22:55
So its an extra 5th gear?

---------- Post added at 22:49 ---------- Previous post was at 22:48 ----------

I've been driving for eighteen year and wonder why there was a 6th gear.

My car has a 5th gear and this keeps the revs low.


This is a windup, isnt it! :Yikes:

homealone
24-02-2007, 22:58
I just bought a new bike with 18 gears ;)

'low' gears do acceleration

'high' gears do speed, ;)

- presumably :)

Xaccers
24-02-2007, 22:59
Be careful when you go back to your 5 gear car, if reverse is straight back from 5th, you could end up crunching the gears as you try and put the car into reverse on the motorway!
Conversely, don't forget you have 6 gears in the rental car!

Creative
24-02-2007, 23:09
I still try to change into 6th gear from 5th when on the motorway these days. Unfortunately my diesel only has 5 gears. I went from a sporty 6 gear car to an economic diesel when I changed jobs. I get more than 50 percent better mpg out of the diesel tho.

---------- Post added at 23:09 ---------- Previous post was at 23:04 ----------

Be careful when you go back to your 5 gear car, if reverse is straight back from 5th, you could end up crunching the gears as you try and put the car into reverse on the motorway!
Conversely, don't forget you have 6 gears in the rental car!
Most cars don't have synchromesh on reverse deliberately to stop you putting a car into reverse at speed.
A few years ago I remember reading about a motoring journalist ruining one of the XJ220's on a test drive on a track when he put it into third instead of fifth at speed. The pistons left the block I seem to remember.

Wicked_and_Crazy
24-02-2007, 23:10
I still try to change into 6th gear from 5th when on the motorway these days. Unfortunately my diesel only has 5 gears. I went from a sporty 6 gear car to an economic diesel when I changed jobs. I get more than 50 percent better mpg out of the diesel tho.

Mazda 6 diesel sport has a 6 speed box

homealone
24-02-2007, 23:10
yes I nearly put a car in reverse gear at 'motorway speed' - luckily my clutch feedback said not ;)

Wicked_and_Crazy
24-02-2007, 23:13
So its an extra 5th gear?

---------- Post added at 22:49 ---------- Previous post was at 22:48 ----------

I've been driving for eighteen year and wonder why there was a 6th gear.

My car has a 5th gear and this keeps the revs low.


18 years ago you were most likely driving a 4 speed car. They principle holds true when moving from 4 gears to 5

Xaccers
24-02-2007, 23:19
I still try to change into 6th gear from 5th when on the motorway these days. Unfortunately my diesel only has 5 gears. I went from a sporty 6 gear car to an economic diesel when I changed jobs. I get more than 50 percent better mpg out of the diesel tho.

Most cars don't have synchromesh on reverse deliberately to stop you putting a car into reverse at speed.
A few years ago I remember reading about a motoring journalist ruining one of the XJ220's on a test drive on a track when he put it into third instead of fifth at speed. The pistons left the block I seem to remember.

I had a sporty 6 speed diesel Megane (and before that a sporty speed diesel Laguna II) that went into the body shop when a lorry look off it's wing while it was parked outside my house.
Was given a Micra (and for those who speak Micra, yes, it is shiny and bright) with only 5 gears.
Ended up crunching the gears a couple of times trying to put it in reverse where I thought 6th should be.
I found shouting "go go micra power" didn't help much when over taking other cars though.

Dan_Sette
25-02-2007, 02:01
no, its higher than fifth, the high to low ratios have just been divided into 6 rather than 5

Ours go up to eleven. Which is, like, one more.

keithwalton
25-02-2007, 02:43
Originally 4th gear used to be 'straight through' (1:1 ratio) the gearbox so it was more efficent to do so.
This was with 4 speed boxes, then they moved to 5 speed boxes and kept 4th gear as straight through. top speed was set as peak power in 4th gear.

The 5th gear was added as an economy gear as most people dont drive at top speed all the time. (Better matching of avaliable power at engine speed to power required for vehicle speed)

some 6th gears have been added as a second economy gear (keeping 4th straigh through for top speed) gearbox technology has advanced alot over the years and are now efficent enough that running a straight through gear has little advantage. So gears are just spaced out to maximise acceleration / ecomony.

A car with 6 gears will accelerate faster than one with 5 or 4.
6 Speed boxes are becoming common with French and Japanese cars