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Hi Martin,

You'd be surprised how many engines still make two with two valves per cylinder (i.e. eight valves in a four-cylinder engine) and actually, more valves are not always better. Generally speaking, an eight-valve engine has better low down torque, where as a 16-valve design allows freer flowing gas at higher engine speeds, releasing more power. However, the eight-valve engines are often more rugged and reliable and of course cheaper to produce.

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Hi Chris,

It would depend on the year and model, but the previous generation Mondeo with the 2.0 TDCi diesel engine, needed its timing belt done at 200,000km or every 10 years.

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Hi Eddy,

I presume you mean the last, rather than current generation. Quite a nice car, actually, majoring on comfort and economy rather than pin-sharp handling and there's that fixed-hub steering wheel and central digital instruments to liven up the cabin. 

Best version to go for is either of the 1.6 or 1.4 HDi diesel models - the 1.4 petrol is just not up to scratch, although the rare 1.6-litre petrol Sebastian Loeb rally edition is worth seeking out as a rare slice of warm hatch - if that's your sort of thing.

In terms of reliability, it's a bit of a mixed bag. There are no huge mechanical issues, but you've got to watch for electrical glitches in the speed limiter and cruise control systems and keep an eye out for disintegrating cabin trim. 

You also have to make sure that all five of the safety recalls have been carried out, including ones for electrical fires, poor brake performance and faulty airbags.

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Hi Gerard,

It’s a very good family car from the point of view of safety and comfort, and yes that 1.5-litre diesel is hugely economical (you should see better than 50mpg on a regular basis). You just need to keep a close eye on electrical items such as the central locking, the key-card and the windows and beware of traditionally steep depreciation for large French cars.

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Hi Gerard,

I write this as a former (recovering?) Laguna owner and the best I can tell you is to tread very, very carefully. Admittedly, I owned the previous generation Laguna that was quite simply a reliability disaster and one that cost Renault a fortune in warranty claims. The third-generation car, the one you're looking at, is much better in reliability terms, but still, you need to be suspicious of anything that uses electricity – make sure absolutely everything electrical is working properly and watch it like a hawk to check for failures. The 1.5 dCi engine is actually pretty good, and robust too, and you should pretty easily get high-forties mpg out of it. However, you're going to be on a pretty steep depreciation slope as nothing loses value faster than a big French car. That's fine if you're planning to keep and use it until it dies, but not so good if you're planning to trade-in in a few years. As a family car, it's actually quite good though – spacious and comfy, with a big boot and Renault has an excellent reputation for safety too.

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Hi Seamus,

A Mondeo 2.0 TDCi is, frankly, a great choice - spacious, comfy, well made and superb for that kind of long-haul journey. Just as a suggestion though, it may be worth coming down a class and having a look around, just as a way of potentially keeping your running costs as low as possible. Perhaps a Honda Civic diesel or a Skoda Octavia TDI? Both are massively spacious (so would carry your height with plenty of space behind for baby seats etc.), but would also be a little cheaper to run than the Mondeo, and almost as comfy on the long haul. Worth a thought, but if you fancy the Mondeo, go for it. Buy one with a full service history and you won't go wrong.

Let us know which way you go in the comments below.

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Hi William,

There are three engines available in the latest Corolla, and though we assume you mean the 1.4-litre diesel, here are all the official figures for completion:

1.33-litre petrol model: 50.4mpg (5.6 litres/100km)

1.4-litre diesel model in Terra grade: 74.3mpg (3.8 litres/100km)

1.4-litre diesel model in Aura or Luna grade: 72.4mpg (3.9 litres/100km)

1.6-litre petrol with automatic gearbox: 50.4mpg (5.6 litres/100km)

Note that these figures are all official 'combined cycle' results and don't usually reflect what drivers achieve themselves. 

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Hi Bill,

There’s no one blanket answer to this, as much depends on where you do your mileage and how you drive. Basically the issue is one of heat. The DPF needs the exhaust system of the car to reach full operating temperature in order for it to burn off the excess carbonised soot that it filters from the exhaust. If you don’t generate that heat then the DPF gets full and clogs up and causes problems. So, you can do relatively low mileage, but if it’s mostly on the motorway and you’re running at a constant 120km/h for, say, 30 minutes or so each day, then you probably wouldn’t have any problems. If you do lots of miles but they’re all in town, stuck in traffic, creeping along, then it doesn’t matter how much mileage you do, you’ll have problems. As a rule of thumb, we usually say that circa 20,000km a year is the changeover point, but as I say, driving style and where you do your driving enter into it too.

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Hi Jimmy,

Really good car - no surprise it's one of the top-selling SUVs. Much better to drive than is the norm for such cars and with decent economy too. No major reliability scares either, just make sure that the recall that saw 800,000 Tiguans worldwide brought back in last year to have a headlight fuse issue fix has been completed. Oh, and the boot is a little on the small side for a car this size, but otherwise it's a good 'un.

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Hi Mervyn,

Generally speaking, most car makers design major parts such as engine heads, blocks etc. for a life of around 400,000 to 500,000km. That said, if you look after the car properly, keep it serviced and be prepared to spend the cash to replace major components from time to time, the total life is essentially unlimited. It’s all down to the care the car gets a lot of the time.