Volkswagen uses the name Alltrack to denote the kind of car that is labelled, among others, by Audi as the allroad, Skoda as the Scout and Subaru as the Outback. In every case, what we're talking about here is an otherwise conventional estate reworked to offer a little more off-roading potential thanks to four-wheel drive, increased ground clearance and a certain amount of underbody protection.The estate in question here is the Passat, of which there are two Alltrack versions. One uses the familiar 2.0 TDI turbo diesel engine in 138bhp and has a manual gearbox, while the one tested here - the most expensive Passat of all, at £31,030 - has a 168bhp version of the same engine and a six-speed DSG twin-clutch semi-automatic.It's a handsome car, and one that caught the imagination of many friends who saw it during this test. Compliments abounded. I quite like the look of it myself, and I was particularly happy that, in sharp contrast to so many cars on sale these days, it has a sensibly-sized windows which offer plenty of rear visibility. (Side visibility is limited by the very thick central pillars, but I suppose you can't have everything.)On forest tracks, the work that has been done to convert this from a strictly tarmac-only estate is very obvious, and equally effective. I didn't go to the extent of testing the underbody protection, but every time the Alltrack encountered a bump or a pothole or a really rough patch it behaved as if this was what it most wanted to do. If, for whatever reason, you need to tackle this kind of road on a regular basis, it has a lot going for it.It isn't as happy on tarmac. It's not uncomfortable, exactly, but the higher centre of gravity induces a lot of body roll, and it never feels properly settled - the slighest undulation is followed by a recovery process which usually continues until the next undulation presents itself.A car like this will always be compromised between the two kinds of driving, of course, but I think other manufacturers have made a better job of it. And if I wanted to buy a Passat Estate (which I might well do - it's a splendid car in many respects) I would avoid the Alltrack unless the requirement for its off-road ability was absolutely crucial.The four-wheel drive system and the increased ride height both have a negative effect on the car, though Volkswagen has tried to limit the effects by fitting start/stop and, on the DSG model though not the manual one, a coasting function which comes into play every time you take your foot off the accelerator.The combined result of all that is fuel consumption of 47.9mpg and a 155g/km CO2 rating, both of them naturally inferior to a non-Alltrack model with the same engine. In what I consider to be normal driving (rarely using the full performance but not particularly trying to save fuel) I averaged over 40mpg but never more than 45mpg on every journey. With a little more care, the official economy figure should be easy enough to match.Like the normal Passat Estate, the Alltrack has enough passenger space to be able to carry four six-foot adults without any trouble, and there's plenty of room for luggage. 603 litres with the rear seats in place and 1731 litres with them folded compares very well with the Ford Mondeo Estate and Vauxhall Insignia Sports Tourer, and also handsomely beats the conceptually very similar Audi A4 allroad, whose pricing starts where the Alltrack's leaves off. Engine 1968cc, 4 cylinders Power 168bhp Transmission 6-speed semi-automatic Fuel/CO2 47.9mpg / 155g/km Acceleration 0-62mph: 8.9 seconds Top speed 131mph Price £31,030 Details correct at publication date