I was checking my air filter (6 months after service) and it was really dirty, full of grit and dust; the airbox was also full of leaves and grit. I've had the K&N for 2 years but never got around to fitting it, until now!

The car really seems to pull stronger and the gauge indicates slightly better mpg. I think its the fact that there is a new filter in it rather than being a free flowing one specifically. I'm not convinced that it would make that much difference to such a heavy car. What do you think?

Sorry to say it, but what I think...is that you should take it back out again...

The K&N filters to don't play ball with the MAF meter(s) and they aren't highly regarded for good filtering etc. My recommendation is to stick with the standard filter but replace it more often.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

Oh b****r! Didn't think about that! The old one was so bad I've chucked it in the bin! A quick trip to the dealer tomorrow methinks!

Good advice by the way!

No need to pay dealer prices: http://www.advancedfactors.co.uk/phe000112...4-81-p.asp Order it tomorrow/now and it should be with you on Tuesday.  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

and a lot cheaper than the k and n filter

Isn't the k and n filters just all hype? Isn't the standard factory ones fine enough?

I agree, it probably makes no difference at all; it's just that I had it on the shelf and fitted it cos the standard one was really really grubby.

send it to me if you dont want it lol

The only real issue with the K&N's that I have experienced is the mass marketing that they can be used over and over again making you think they are better bank for the buck. The reality is that you have to wash and re-oil it using THEIR products then you have to worry about the oil clogging up the MAFs. I had one with my old Audi but took it out in favor of the OEM filter. For me all the hassle of owning these things is just not worth it. Go OEM and just slap them in and you're done for a year.

Oh and yes the car will pull better and get you better mileage at the expense of engine wear as there is NO WAY that a thin cotton cloth is gonna filter out as much as a thick paper filter. There is always a trade off some where.