My journey to and from work is mainly pretty free flowing B roads, 30 and 40 zones and a short derestricted section with only a few minutes of stop start at a big roundabout near the office - it's about 9 miles each way.

My TA 4x4 was showing average consumption of 48.9 mpg for this journey. However, for the last four tankfulls I have added Redex and the mpg has climbed steadily, topping 50 and this morning reached 52.2.

Some time ago I did try regular fills with Super Unleaded, but got nothing like the mpg returns above.

Just thought you might be interested.

I'd be very pleasantly surprised to achieve any of those consumption figures - in 60,000 mles the best my 4x4 TA has managed is 42mpg.

babbo_umbro said:

I'd be very pleasantly surprised to achieve any of those consumption figures - in 60,000 mles the best my 4x4 TA has managed is 42mpg.

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Ours has 30k on the clock and average is 41.5.

I should have mentioned of course my '64 reg has 21k on the clock.

babbo_umbro said:

I'd be very pleasantly surprised to achieve any of those consumption figures - in 60,000 mles the best my 4x4 TA has managed is 42mpg.

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Me too.

Last weeks driving in my Cross TA, 323 miles, 55.6mpg. A typical week of commuting and recreational use. Total mileage nearly 70k and the average weekly economy rarely below 50mpg. Even allowing for 5 to 10% error on the trip computer it's still good economy.

James The Butler said:

...However, for the last four tankfulls I have added Redex and the mpg has climbed steadily, topping 50 and this morning reached 52.2....

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This sounds good. But, like all 'experiments', it needs a 'control' -- an identical car making the same journey without changing anything -- to give a comparison.

Other factors may be at work here. For example, the weather is warmer, which not only affects the air entering the engine, but the temperature of tyres and the road surface, and owing to that, the rolling resistance. Its rained less (here in Hertfordshire at least), so the electrical drain of the wipers and blower fan are different...

One of the recent weeks was half term, so less traffic overall...

It could be the Redex, or it could be other factors, or both. You might never really be sure.

My 'old' (2013, and 66k miles when sold a couple of weeks back) 4x4 MJ always did better in the summer (60 plus in summer, 56 lowest in winter). My nearly-new one is only on 2500 miles and so far only reaches 52 mpg... but is also Euro 6 so hard to compare.

PaulD said:

Last weeks driving in my Cross TA, 323 miles, 55.6mpg. A typical week of commuting and recreational use. Total mileage nearly 70k and the average weekly economy rarely below 50mpg. Even allowing for 5 to 10% error on the trip computer it's still good economy.

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How?

How?

A combination of happy circumstances. A 25 mile commute to work on a carefully chosen route such that there is no traffic and few junctions to negotiate. A near constant 30-40mph. Undulating terrain with short, gentle gradients.

Having said that I recently completed a 1600 mile trip to Uig in North Skye and back plus local travel on Skye. There were two of us travelling and returning with a further 70kg of samples. The return leg was completed in 11 hours with long motorway and A road stretches on the A1, M6, and M74 at an indicated 52.4mpg.

I've cracked it.

PaulD must have bought the car that Fiat used for the official mpg tests. It's been fettled to the nth degree, to give extraordinary results. The panels are probably aluminium, and the oily bits are titanium.

It's the only explanation that makes sense!

PaulD said:

How?

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No cold, steep hills, ever - simple as that I reckon.

Temperature certainly makes a difference - I get a couple more mpg for the five months (spring and autumn) I'm in Italy compared with Devon. Both have light traffic, both are hilly, Umbria exceptionally so, but a 20-25% discrepancy in average consumption is still surprising. Must be to do with driving habits - I treat the TA like any other petrol engine, keeping the revs between 2000 or so and almost 6000, don't do any flogging in high gears, tend to do 70 mph on dual carriageways, 80mph on motorways, perhaps a few more on autostrade and autoroutes (when cameras allow).

I've tried the gentle approach - avoiding dual carriageways, pootling along at 40-50, using the highest possible gear, no hard acceleration or braking, avoiding town-centre traffic and hills (not hard in these parts) and even then, I can't get better than 48 on a tankful. Deathly boring way of getting around, too.

For comparison, I borrowed my wife's new V40 diesel for my commute to Norwich this week, and on the same roads, in a car with a tight engine (only 200 miles on the clock), and driving exactly the same way, I'm getting a comfy 72 mpg, so I don't reckon its my driving style.

I'm using ECO a lot now on my TA 500, last tank with mixed conditions was 51 on the trip. Would easily and have got over 60 on a long run. I've 40K miles up now and I have to say ECO is really nice to drive with particularly around town as it's much smoother, you notice it a bit on hills but even still its very usable compared to when the mileage was lower when it wouldent pull you out of bed! Normal mode has now become 'sport mode' and i bang it on for overtaking if necessary. The warm weather does make a big difference though in terms of performance and economy.

Mercky said:

I'm using ECO a lot now on my TA 500, last tank with mixed conditions was 51 on the trip. Would easily and have got over 60 on a long run. I've 40K miles up now and I have to say ECO is really nice to drive with particularly around town as it's much smoother, you notice it a bit on hills but even still its very usable compared to when the mileage was lower when it wouldent pull you out of bed! Normal mode has now become 'sport mode' and i bang it on for overtaking if necessary. The warm weather does make a big difference though in terms of performance and economy.

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Interesting - I tried Eco on my 4x4 TA when it was almost new and was frightened by how lethargic it was - so slow I kept waiting for someone to hit me up the rear. Haven't tried it since.

babbo_umbro said:

Interesting - I tried Eco on my 4x4 TA when it was almost new and was frightened by how lethargic it was - so slow I kept waiting for someone to hit me up the rear. Haven't tried it since.

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It does take a bit of getting used to initially when you switch over but then it just becomes normal, not sure on a 4x4 if it would be as usable as maybe you’ve different gearing but try if for a week and you might be surprised

The Redex has worked, lot more free revving. Meant to divide bottle over couple of tanksful so I will. Had to dig fuel funnel out to pour in due to the anti siphon fuel flap. Economy won't be affected (still around 30mpg, worst just under 28 worked out with calculator other week). Apparently Honest John got 35mpg out of 500 TA Lounge press car he had in 2010. Not surprised really.