Rule of thumb says the correct on-road pressure is somewhere between 30 and 40psi for tyres like these. But since you’re losing traction regardless of inflation pressure, who knows. Clearly something else is going on here. Just for starters, the MU-X is fitted with both traction control and stability control which should rule out losing traction in the first place. Are these systems working? If not, you’re technically driving an unroadworthy vehicle.

How old are the tyres? Were they fitted to your previous vehicle and swapped over to the new one? Tyres have a finite lifespan beyond which the rubber compound starts to degrade and the tyres lose grip. That’s something to check. Perhaps the rubber has been contaminated by something like oil or grease. Has the vehicle ever been parked in a pool of oil or diesel? It sounds pretty daft, but is the fuel tank or filler neck allowing diesel to leak on to the tyres or flick up on to them as you drive?

You also need to be aware that as an off-road tyre, on-road grip will never be as good as a tyre designed to work mainly on bitumen. The tread pattern and compound are both compromises in the interests of going off-road, so you can’t expect passenger-car tyre grip from a tyre like this one on a vehicle like your Isuzu.

This make and model of tyre seems to be pretty well received among users, although some have mentioned a lack of wet bitumen grip as something to keep in mind. Don’t forget, either, that in really wet or greasy conditions, you can safely switch to high-range four-wheel-drive to prevent wheelspin and improve your safety margin.

This is probably a simple case of an automatic transmission doing what it’s designed to do. In order to keep the engine in its comfort zone (and making sufficient power and torque to haul the caravan at the speed you’ve chosen) the transmission will shift through its gears to achieve that happy balance.

Any time you encounter a hill or even a headwind (and it’s more so with a heavier caravan) the transmission will assess what speed you want to hold, and then (via changing gears) keep the engine at a speed that supplies the necessary performance. Even a hot day can cause a change in the shift patterns as the transmission aims to take the strain off the cooling system by giving the engine and easier time. Again, a big, heavy caravan will amplify this effect.

However, if the transmission is changing gears for no apparent reason, then you may need to have the calibration checked and perhaps even reprogrammed. Don’t forget, though, that a modern transmission is a pretty clever piece of gear that can even choose to shift down gears going downhill to take the strain of the vehicle’s brakes. Don’t confuse an active transmission with a dud one. And if you still think the behaviour is odd, then an electronic scan of the vehicle might provide more information.

Okay, here’s the bottom line: All engines use a little bit of oil. If they don’t there’s either something wrong with the oil pump, or the owner is kidding themselves and not checking the oil level correctly. Modern turbo-diesels also 'breathe' a little oil back through the engine as part of the emissions control system, and owners with an aftermarket catch-can system often find a bit of oil winds up in there instead of being burnt in the engine.

The question is how much is too much. I don’t think 700ml per 2000km is excessive and your dealer’s views will be based on the official figure from Isuzu. But in the real world, owners are reporting oil consumption of around a litre to 1.5 litres per 5000km. At which point, your engine is right on the money.

How you drive the vehicle and whether you tow a heavy load will also affect oil consumption, as will ambient temperature and the type of oil you use. It’s a fact that modern, lower-friction engines are designed to use a little oil in the name of saving fuel, and it’s something car owners need to get their head around. Keep an eye on that dipstick and you should be fine. Checking the oil on a regular basis will also tell you whether the engine’s drinking habits have changed; a much more valuable piece of knowledge to have.