AdBlue

[LukeC]

How long should a tank last before the light comes on? I figured that the garage I bought from had given a service and top up of the adblue before sale, and I've done just over 12k since purchase, with no warnings about the adblue needing a top up. Is this normal, or should it have warned me by now?

[evdama]

That's about right I'd say.
Our Merc sprinters at work go about three months on ten litres.

[notsofast]

The possible range can vary a great deal, depending on the vehicle and how it's driven.  The manual for my K9 1.5HDi says it has an AdBlue tank holding 17 litres, giving a driving range of 3,700 miles, yet I usually get about 6,000 miles after putting in only 10 litres.

[LukeC]

I've only ever used adblue in buses before, and they drank it. For me, as a van, I'm driving at 60 on the dual carriageway, and a lot of my time is around town or short bursts of dual carriageways. I'm always aiming to get the best economy and getting around 52mpg in general. I would like to think that it's just efficient driving and it'll come on with some kind of warning eventually. Rather than me stressing that I've got a fault with no warnings.

Thanks evdama and notsofast.

[Harrythephot]

Keep it topped up though, or use an additive to help stop it crystalising and borking the pump / pressure switch / pipes.

[LukeC]

Keep it topped up though, or use an additive to help stop it crystalising and borking the pump / pressure switch / pipes.

I hear mixed reports of when you should fill up or top up the adblue. Some people keep topping it up regularly, others only once the light is on and a minimum of 5 or 10 litres to clear the warning.

I've heard with topping up regularly, that the light will come on because it hasn't registered a full up because the warning hadn't been activated, and then might be too full to take enough to clear it.