For some time I've been bothered about how filthy the engine and under bonnet areas get. It seems that there is no sealing on top of the radiator housing. I experimented with various things and found that a length of 22mm pipe insulation zip tied above the radiator seems to work. I also pushed two short lengths of insulation into the gaps between the headlamps and the radiator area. It all looks a bit crude but certainly worked in the last week when local motoways were very wet and salted. The attached photos hopefully show the idea.

Good idea that I like the stone catcher too I have one on the bottom grill save them hitting the cooler

Yes, good idea.

They have put an undertray on the cars to stop crud coming up but then it gets in through the front anyway, seems a little daft.

The 06 Navara I used to drive had a rubber seal (as you get on the doors) all the way round the bonnet area to do what you have achieved and that really did work well.

Steve