missfixit70 wrote:If the sediment light comes on, not necessarily necessary to change the filter, that's why it's got a drain in the bottom, could just be a bit of water that needs draining out
Also, Most of us only change the oil filter every other oil change (10,000km or longer if using semi synth oils)) & air & fuel filter's recommended replacement interval is 50,000km - all as recommended in the owners handbook

I'd still change the fuel filter, they cost next to nothing, and if you're getting water in you fuel, more the reason. Ask yourself why is here water in the fuel tank? Too much condensation with keeping an diesel tank only half full in colder weather, then water forms on the top of the inside of the tank, very fine droplets, but all those droplets are water. We fuel every vehicle up at the end of every day to prevent moisture build up.
Changing the filter with your oil is common practice over in New Zealand. All garages offer this as part of a vehicle service schedule
I work in a workshop, servicing and repairing the trucks in our fleet. It's company policy to change the smaller vehicles filters when you do an oil change, and the high milers get services with oil change and filter every 5,000 km's. We get trouble free motoring, bugger all breakdowns. Medium size vehicles, (three to ten tons are every 10,000 km's The bigger vehicles, (over twenty ton) get a full service every 20,000 km's.
Different strokes for different folks,but preventative maintenance is cheap insurance in the long run.
If you live in a smoggy or dusty surrounds, take your air filter out after 5,000 km's and see how much dirt/dust is accumulated in the folds of the filter. I work and live in a really green atmosphere, and the mileages I said earlier are what most Kiwis undertake with changing their filters etc.
Maybe in the UK, their is no car fumes. smog, dust or the likes in your daily travels, but I would have thought your congestion would add rather than subtract to making your air filter dirty. The intake on a Bong is only about 30 inches off the ground.
One of the best reasons for poor performance is a dirty air filter. All diesels need both fuel and clean air to operate, without they simply don't go, and dirty fuel leads to injectors becoming clogged, so once again, preventative maintenance is cheap insurance policy and gives both peace of mind motoring plus a longer engine life.
See what happens missfixit70 when you push my buttons, I get all explainith (if there is such a word) Now happy motoring, and keep up the smiles.