Thread: Discovery TD 3 Vs 2.7 Fuel economy

I have a MY12 3.0 SDV6 3.0 and my brother a MY11 TDV6 2.7. We frequently do trips together and I know there are lots of other variables. Both are 6 speed.

But for what it is worth.

On roads, dirt and off-road rock and bush tracks, the fuel use is similar or favours the 3.0. Across the Simpson the 2.7 used about 20 litres less. We went a long route not just straight across. In the Simpson we felt that the tyres played a role. He has 18inch wheels which means that he also has wider tyres etc. He seemed to traverse the sand slightly better. The difference was small, we both climbed Big Red "the hard line" etc. In summary the difference in fuel consumption between these two cars is small.

Now I have GOE 18 inch wheels (just fitted) and when we next do a sand trip it will be interesting to see if things are different.

I had a 2011 2.7 D4 I recently traded on a 2013 3.0 D4 (155kw).

Not that the 2.7 was gutless, but it wasnt a rocket, and so the car was happier being driven gently.

The 3.0 twin turbo has much less lag, and far more get up and go. So I drive the new car far more "enthusiatically".

That said it still gets better fuel economy.

The 2.7 used to get about 650km per tank, the 3.0 gets 750km under the same circumstance, I did manage to get the last tank down to 650 but most of that was spent towing 2T of gravel/sand/firewood.

Another thing of note is the rpm, but the 2.7 would always stay in a gear that kept the engine at about 2000rpm. I assume to always remain up in the powerband to help hide the low down lag.

There is one low speed corner up a hill on the way home that caught it out.

The 3.0L with an 8 speed is happy to let the rpm drop to 1200 sometimes lower. Yet the corner that had the 2.7 struggle and need the pedal pushed to the floor to get going again is not a problem to the 3.0.

Not sure if its the engine, the two turbos or the 8 gears, but is all works much better, faster, quieter and uses less fuel.

FWIW I have a spread sheet on fuel consumption since new and I do not drive for economy. My last fill at 68,000 has me at 11.07L/100 average which I think is great overall. (2012 3.0 SE)

Bear in mind that the economy tests are partly done in a lab. This can distort the figures from the real world tests as they probably don't represent the physics of moving the vehicle around accurately enough, where the larger engine will have an easier time of moving a given weight, so it could be seen to favour a smaller engine.


I prefer to rely on good motoring publication test results to get an idea of a cars economy.


The fuel consumption testing scheme

I have been thinking and wondering.

I have heard that the TDV6 3 ltr may have twin turbo - is this true ?

It could also be that the TDV6 2.7 may need to go to the Dyno to tune the turbo for an additional tuning to either get power or fuel efficiency.

Surely 300ml can not make that much of a difference alone !

I remember that when I had my Turbo installed on my Nissan I was able to tune it at the Dyno to achieve either max power or max economy as a benefit. At the time as a younger lad I went for POWER !!!!!! and it was a monster - it featured in one of the popular 4WD magazines.

These days I am more relaxed, will have to pay the Dyno fees then.

I agree the UK government website would be more reliable data.

Regards
Tor

Originally Posted by Torero22

I have heard that the TDV6 3 ltr may have twin turbo - is this true ?

Correct....all 3 litre diesel D4's have two turbos.

From what I have read on aulro, my 3 litre uses considerably more fuel in all situations than the 2.7

Brett....

People that have gone from 6 speed,2.7 or 3.0l seem to say the 8 speed uses less fuel.And that is both the HP and the LP 3l engines.

Real life driving fuel usage is usually different to what is published.

Originally Posted by discotwinturbo

From what I have read on aulro, my 3 litre uses considerably more fuel in all situations than the 2.7

Brett....

So does mine, Brett. I never get better than about 12.5 l/100km in any conditions, although the trip computer tells me otherwise. Maybe the ECB bullbar and Kaymar rear bar create a lot of extra drag plus the extra weight of these and the extra battery and long range tank etc.

Bob