Merry Christmas to Everyone .New Oil!

Any good oil should last around 10,000km if it has decent recognized properties.
Do K&N make their own oil filters? Didn't now that.
If the filter is any good at all, it should last at least one oil change period.

14000 micron is smaller than 60,000mircon so what you said is Frack to Bunt, isn't it? I think it is.
Ryco being the finer filter than the stated K&N
Never used a K&N filter.
A 60,000micron will let through bigger blowflies than a 14,000 item.

PS. 90 to 100 is a normal speed, can't see why it is grandad pace.
120kmh with a 3 ton van on should be ok for some.

Yes well a 5micron filter is a much finer one than a 10 micron one so think the guy is full of the brown stuff that wont filter too well..
As per here
https://inspiredliving.com/cuzn-water-filtration/micro-rating.htm
What is the brand of oil. Not much good saying what it does without that.
Twice a year . Hmmm what about kilometers covered is a better way. Some cars like mine would only do 8000 a year some would do that in a couple of months. The only real way to check if consumption is better is do the same trip twice in the same time in the same weather and similar road traffic conditions.
Once with the old oil and then with the new.
Is a bit like the placebo effect in drug trials Half get the good stuff and half get a sugar pill Amazing how many report improvement after taking the sugar pill.
Why because they want to believe it has helped them.

There is so much utter BULL$#$@ going around about oils..... some of it very convincing.

Most mechanics ( like most tradesmen these days) are not all that clever or well informed, so they are as much prone to being suckered as anybody else. I have met several who believe in crackpot things. .... there are also those who simply want to make money by selling you something you probably don't need.

Pretty much any reputable diesel spec oil, is well and truly capable of running oil change intervals in the 100 000s of Km ...... In the right engine under correct managment ... they are pretty much all "High drain interval oils", it's part of the spec.

As I mentioned in other posts it is not the properties of the oil that determine oil change interval in diesels, it is the carbon load and the filtration system.

Some people have claimed that we should be changing the filters and not the oil .... that sort of holds water but only to a point.

There have also been various ultrafine filtration systems marketed at various times, but they have their issues too.

Here is why ..... the carbon particles in oil vary in size ranging from in the order of 1000 microns down to the order 0.25 microns. It's a very wide size range.

Human hair diameter is from about 30 to 100 microns.

Good quality oil filters typically capture about 70% of particles in the 8-10 micron range and and more of the larger particles. Cheaper filters capture less than 50% of the 8-10 micron range particles.

There are fancy aftermarket filters that claim to capture 95% of 8-10 micron particles and continue to filter efficiently down into the 5 micron range and below.

But that still leaves all the finer particles flowing straight thru the filter and remaining in the oil.

This is why, used diesel oil is like ink .... black and stains everything it touches.

We have to face facts that most of the small diesels, particularly the pre 05 non common rail diesels are dirty little engines that have large quantities of carbon passing the rings and ending up in the oil.

use of super fine aftermarket filtration WILL extend the drain period of whatever oil is used ..... but you will be changing the filters more often as they will clog far more rapidly

there is a trade off between having to change the filter too frequently and filter efficiency.

As I said .... pretty much any reputable diesel oil will last many times the oil change interval most of these small engines run, if it was not for the carbon issue.

It has been argued reasonably that using reputable diesel spec oil and quality after market filters, the drain interval on small pre05 diesels could be extended from 5000 to 10 000 Km by changing the filters only .... the detail of the argument varies.

Remember pretty much all of these diesels run better on fresh oil ... any fresh oil.

cheers