VE 4 speed auto, 5 speed auto RPM at

[rudi]

Hi all
I have been planning on getting a series 2 sportwagon but I don't think I will be able to afford one .
I do a lot of highway ks and a bit of hills so I would like a economical cruiser.
I understand the 5 speed auto apparently uses a bit more fuel than the 4 speed auto?
I wonder why?
The specs say top gear the 4 speed has ratio 0.7 and the 5 speed has 0.75. not a lot different to make that much difference I would have not thought.
So
at 100km/h what RPM are each gearbox reving at
at 110km/h what RPM are each gearbox reving at

If the diffs aren't the same maybe fit the 4 speed auto diff into the 5 speed car? To lower the RPM at highway speeds. Maybe an option?

Thoughts?

 

[Zeke Topanaga]

I don't think that the 5sp auto is as reliable as the 4sp ones.
The cost conversion would cut out any savings for you I would say.
Going up to a higher diff ratio would not do much at all really over all in saving fuel.

 

[rudi]

Thanks Zeke
Not as reliable ?
Still wonder why a 5 speed isn't as efficient as the 4 speed?
Im tossing up between a
2010 3.0 litre omega wagon 150000ks $10,000
and a
2009 Calais wagon 5 speed auto 125000ks for $12,000

Tassie prices suck compared to the mainland.

 

[greenacc]

The 4 speed box was used by GM for 30 something years because it's a tuff unit.
The 5 speed was only good for the salesman to sell as an upgrade cos more speeds... don't mention the fact it costs 3 times as much to maintain and I bet is a heavier unit to add to fuel costs.

 

[rudi]

If the extra gear was just a selling tool, then the same must be said for a 6 speed.
Are you saying a 6 speed is no more efficient than a 4 speed?

 

[Zeke Topanaga]

If the extra gear was just a selling tool, then the same must be said for a 6 speed.
Are you saying a 6 speed is no more efficient than a 4 speed?

No the 5 speed helped make the 3.6L perform better as does the 6 speed auto
I think the old 4sp was 2200RPM at 100KM/H and the 6speed is 1800 ? I will have to look up about the 5speed ratios.
The thing about the 3.8L it has grunt down low and the 3.6L does not, so she needs more gears, so a lower ratio in 1st helps the 3.6L a lot with the 5 gears.

 

[greenacc]

If the extra gear was just a selling tool, then the same must be said for a 6 speed.
Are you saying a 6 speed is no more efficient than a 4 speed?

Nah, I'd buy a 6 speed but am happy with my 4 speed for as long as it lasts.
I think the reason the 5 speed makes little difference to the fuel economy is you barely use that extra gear. The 4 speed in the VE is quite well matched to the car I think and particularly on highway it sits on top gear most of the time so having extra gears your not using will do almost nothing.

 

[Zeke Topanaga]

I find with the 4speed auto in the VS and with the hills on the highway around, it takes a fair hill for it to drop back to 3rd, but with the 6sp auto on the same hills at 100KM/H she drops back to 5th and then back to 4th a fair bit normally when your coming near to the end of the top and with cruse control on that inertia will push the car forward driving up your speed by around 3KM/H easy and if you are then just starting to going down hill it can go to 110KM/H quite easy and then you spot the f ing speed camera, f I don't remember how many times that happened going from QLD to SA.
Them bastards are always sitting in a spot where your cruse control will get you into trouble and you know that every K over is a killer, so their Nazi propaganda of zero tolerance can not be dismissed and your f ed over paying big $ and points for just moronic propaganda crap.

 

[VS_Pete]

I don`t put cruise control on when in the hills.

 

[commodore665]

No the 5 speed helped make the 3.6L perform better as does the 6 speed auto
I think the old 4sp was 2200RPM at 100KM/H and the 6speed is 1800 ? I will have to look up about the 5speed ratios.
The thing about the 3.8L it has grunt down low and the 3.6L does not, so she needs more gears, so a lower ratio in 1st helps the 3.6L a lot with the 5 gears.

No , at 100 Km/hr the 4 speed ticks over at 1750- 1800 RPM and the 5 speed is the same at 100 KM/hr .Its the final drive that makes the difference , the 5 speed is a sealed unit too , so it makes servicing a little tricky as it has no dipstick .