Can i improve economy of an automatic?

wazza

I am interested in a Vauxhall Zafira 1.9 diesel with a 6 speed automatic gearbox. When in D (drive) i can flick the selector towards left and change the gears manually. When in D i noticed that at around 50mph the car is in 5th gear (dashboard display tells you what gear you are in). I can select 6th gear manually with no problems.


I know that automatics are less economical than manual gearbox. If i change the gears manually can i improve the mpg figures? Hope i make sense.


Before anyone says buy a manual i have problems with my legs and find using clutch a problem sometimes.

cyclonebri1

wazza wrote: »

I am interested in a Vauxhall Zafira 1.9 diesel with a 6 speed automatic gearbox. When in D (drive) i can flick the selector towards left and change the gears manually. When in D i noticed that at around 50mph the car is in 5th gear (dashboard display tells you what gear you are in). I can select 6th gear manually with no problems.


I know that automatics are less economical than manual gearbox. If i change the gears manually can i improve the mpg figures? Hope i make sense.


Before anyone says buy a manual i have problems with my legs and find using clutch a problem sometimes.

In that case the answer is probably yes. However, under normal motoring conditions, you spend an awfull lot of time/(diesel) in and out of lower gears so don't expect anything to radically improove.

Strider590

Auto's aren't less economical, there's no driver control over what gear it uses.

When manufacturers do their fuel efficiency testing on manual cars, they use drivers who change gear at EXACTLY the right time for EVERY single gear change.... 99% of the drivers on the road can't do this for more than a few gear changes.
The "average Joe" won't be able to drive anywhere near as efficiently in a manual car.

So in short, the manufacturers figures are false.

cyclonebri1

Strider590 wrote: »

Auto's aren't less economical, there's no driver control over what gear it uses.

When manufacturers do their fuel efficiency testing on manual cars, they use drivers who change gear at EXACTLY the right time for EVERY single gear change.... 99% of the drivers on the road can't do this for more than a few gear changes.
The "average Joe" won't be able to drive anywhere near as efficiently in a manual car.

So in short, the manufacturers figures are false.

And the figures they produce for auto's aren't??;)

Don't forget if you accelate hard in an auto it will hold back in the lower gear, just as likely to produce false figures as a manual.;);)

Savvy_Spender_South

Don't forget to top up tires with free air at the supermarket forecourts and do not carry loads of clag in the boot. these both effect fuel use.

If you want to maximize efficiency, half fill the tank and use until 15% left. This saves on carrying extra weight in fuel, but re-fill (half) before you reach the diesel sludge.

You can change the spare for a re-fill aerosol to save weight, especially if you have breakdown cover which i guess you do with your medical situation.

Inactive

Strider590 wrote: »

Auto's aren't less economical, there's no driver control over what gear it uses.
.

Of course there is, I can almost dictate which gear that I want to be in, in my Automatic via my right foot.;)

harveybobbles

I've never been able to get over 40mpg from a Vectra/Zaffy 1.9 diesel auto. Infact they have usually been about 36, which is pretty poor when the petrol ones will do 40 easily...

colino

The right foot control is the one to concentrate on and anticipate in advance what is going on and what you want to do. Lots of auto drivers think two pedals think you should be using one of them at all times and my nearest and dearest is one of them. The "stop and go" ride is less than comfortable and the mpg average comparisons tell the tale (23.5mpg v. 29.5mpg) simply due to different driving styles.

Inactive

colino wrote: »

The right foot control is the one to concentrate on and anticipate in advance what is going on and what you want to do. .

Spot on.. :T;)

Sirbendy

indeedy. My old Astra3 1.6 auto would easily crack 400 miles to a tank, more often 450. I drove it with light throttle, if I wanted to overtake etc I'd flick the sports button and let that do a changedown instead of walloping the throttle, it worked beautifully.

People who had Manual Astra3 1.4/1.6s at work were continually whining that they got naff all to a tank (300 miles)..heh.

Now I've got an Astra mk4, 1.6MPi auto...I drive it the same, yet I can barely hit 350 on a tank. Same size tank, same everything bar the MPi (as the Astra3 was SPi), and the fact this Mk4 is drive by wire.

I think on drive by wire autos you're a bit hamstrung..on older cable driven jobbies you could vary the throttle infinitely..on a drive by wire, you only have logical absolutes to work with. That's about the only thing I can see with mine.

I could of course fit the injection manifold from my spare Astra3 MPi into the MK4, but I suspect it'd complain..:rotfl:

Strider590

Sirbendy wrote: »

indeedy. My old Astra3 1.6 auto would easily crack 400 miles to a tank, more often 450. I drove it with light throttle, if I wanted to overtake etc I'd flick the sports button and let that do a changedown instead of walloping the throttle, it worked beautifully.

People who had Manual Astra3 1.4/1.6s at work were continually whining that they got naff all to a tank (300 miles)..heh.

Now I've got an Astra mk4, 1.6MPi auto...I drive it the same, yet I can barely hit 350 on a tank. Same size tank, same everything bar the MPi (as the Astra3 was SPi), and the fact this Mk4 is drive by wire.

I think on drive by wire autos you're a bit hamstrung..on older cable driven jobbies you could vary the throttle infinitely..on a drive by wire, you only have logical absolutes to work with. That's about the only thing I can see with mine.

I could of course fit the injection manifold from my spare Astra3 MPi into the MK4, but I suspect it'd complain..:rotfl:

I think you'll find that the MK4 (G) is somewhat bigger and heavier than the MK3 (F).