Outer Limits 4x4 Board

A friend is after a GU 4.5, is there much difference in fuel consumption between an auto and a manual. He has a tight weekly budget.

It will be on gas and the fuel consumption for day to day driving is his main concern. We know a GU 4.5 is no fuel miser, but he also knows that if fuel was the only factor in vehicle choice then he would be buying a Barina.

Cheers

hi there manual is heaps cheaper to run

Yep, manual will be considerably more economical.

it will depend a LOT on the type of driving he does and the kind of driver he is. The manual is potentially more economical around town however on the highway the auto will probably be slightly more economical. My question would be though, if you are on a tight weekly budget, why would you buy a huge 4WD that will consume 20+ l/100km? there are plenty of more economical vehicles out there that will move the same number of people (eg tarago stylee vans) or go to the same places (eg hilux stylee utes) or tow a similar payload (eg commodore stylee sedans), all while using much less fuel.

that said, for any given vehicle, the single biggest factor influencing fuel efficiency is the driver - I used to drive a 4.5 GU manual for work and could consistently get under 14l/100km on the highway and under 18 around town by keeping the speed down and driving conservatively.

not certain as i havnt had it long enuf to have heaps of evidence, but since getting an auto 3.0td surf i think im using almost twice as much fuel as when i was driving a manual 3.3l diesel patrol that was more than 10 yrs older and about half a tonne heavier....

Autos are for Fags (Nancy's)!

v6hilux wrote:Autos are for Fags (Nancy's)!

oh shite, here we go again....



don flame suit all

dumbdunce wrote: why would you buy a huge 4WD that will consume 20+ l/100km?

Because you want a huge 4WD but are interested to know if there are major differences between tranny types. He has a shack in the high country that he and his mates can use anytime and they all tow dirt bike trailers or campers regularly. He got sick of heading along the 70km of dirt road in a lowered commy wagon with trailer too.

His budget isn't that tight that he can't afford to live a little.

At any rate he got a 98Ti 4.5 auto today.

thanks for the help guys.

v6hilux wrote:Autos are for Fags (Nancy's)!

I wouldn't buy one either But it's not my truck it's his.

dumbdunce wrote:it will depend a LOT on the type of driving he does and the kind of driver he is. The manual is potentially more economical around town however on the highway the auto will probably be slightly more economical.

Why do you expect the auto to be more economical on the highway, is there a gearing difference?

KiwiBacon wrote:

dumbdunce wrote:it will depend a LOT on the type of driving he does and the kind of driver he is. The manual is potentially more economical around town however on the highway the auto will probably be slightly more economical.

Why do you expect the auto to be more economical on the highway, is there a gearing difference?

yes, the auto has a taller top gear. regardless, autos in lockup at highway speed are potentially more efficient than manual gearboxes under the same conditions; less internal sliding contact, thinner oil, finer tolerances. have a look at manufactuer's claimed fuel efficiencies for most cars built in the last 10 years; the autos often have a higher claimed highway efficiency. The biggest vaiable remains driving style; if you drive efficiently, pump up your tyres, keep the speed down, anticipate instead of braking late and acceleerating hard etc, you will use less fuel.

dumbdunce wrote: yes, the auto has a taller top gear. regardless, autos in lockup at highway speed are potentially more efficient than manual gearboxes under the same conditions; less internal sliding contact, thinner oil, finer tolerances. have a look at manufactuer's claimed fuel efficiencies for most cars built in the last 10 years; the autos often have a higher claimed highway efficiency. The biggest vaiable remains driving style; if you drive efficiently, pump up your tyres, keep the speed down, anticipate instead of braking late and acceleerating hard etc, you will use less fuel.

I've been looking pretty heavily at auto vs manual fuel consumption for the last couple of years in fwd cars. The autos all seem to have a penalty of 1km/l or more.
For example my auto shopping basket is claimed 7.8L/100km. The manual version claims 6.7 L/100km.
http://specs.amayama.com/specs-nissan-a ... ust/19778/
http://specs.amayama.com/specs-nissan-a ... ust/19777/

Wiring in a couple of indicator lights and an over-ride switch into the torque converter lockup showed I could gain a little on hills, but not on the flat.

Basically planetarys aren't as efficient as two meshing gears, especially when you get several of them in a row. Throw into account a hydraulic pump on the end of that and you've got a large parasitic loss that a manual doesn't have.