Thread: Air Filter on D4 TDV3.0 HSE?

There have been a number of independent lab tests of after-market 'performance' air filters (most in Europe) such as K&N, and although not unanimous, the overall conclusion has been that they provide less filtering than the OEM-supplied filters. Ben will have the details, as I recall him posting on this before. In dusty conditions you're better off with the slight performance hit of the better-filtering OEM ones.

Cheers,

Gordon

Originally Posted by Disco4SE

Hi Ben,
Not exactly sure where you are coming from? The K&N filter, I believe has a great filtration system. Are you comparing it with having no filter?
As with exhaust systems, manufacturers design filters to 'do their job' as opposed to being the most efficient.

Originally Posted by Disco4SE

Hi Ben,
Not exactly sure where you are coming from? The K&N filter, I believe has a great filtration system. Are you comparing it with having no filter?
As with exhaust systems, manufacturers design filters to 'do their job' as opposed to being the most efficient.

In every independent test I have seen, K&N filters have ALWAYS come out significantly worse in terms of filtration efficiency compared to the OEM filter they are designed to replace.

EDIT

http://www.billswebspace.com/AirFilterTest.htm

Originally Posted by isuzurover

The extra dust actually aids filtration.

At which point does "more clogged " become useless ?

Originally Posted by isuzurover

It may also void your engine warranty

...... like anything , just exchange it before service .

As for engine life , I don't don't think anyone is concerned
about who buys their old vehicle anymore than who buys
their house or is sleeping with their Ex. .............

It really isn't worth asking these filter questions , or who
voted for whom etc . It's the buyers choice ....... and that's that .

Probably sounds like a dumb question, but what is an OEM filter?
Also, I can understand the importance of good air filtration in dusty conditions, however if most of your driving is on road, would the K&N filter be so bad?

I think OEM stands for Original Equipment Manufacturer and it means that the item you are buying will be to the same standard as that originally fitted to the vehicle

Thanks BlackPerth. Thought it may mean along those lines.
Pays to ask sometimes even if you sound like a dumb arse

Originally Posted by Disco4SE

Probably sounds like a dumb question, but what is an OEM filter?
Also, I can understand the importance of good air filtration in dusty conditions, however if most of your driving is on road, would the K&N filter be so bad?

As mentioned - Original Equipment Manufacturer.

As you can see above, in this case (Duramax diesel air filters I believe) the AC Delco (likely "OEM quality") is ~99.9% efficient and the k&N is ~97% efficient. That 3% difference may not sound like a lot, but over time it means a huge difference in the mass of dust getting to your engine. Of course this would be worse if you drive in dustier conditions.

Originally Posted by Disco4SE

As with exhaust systems, manufacturers design filters to 'do their job' as opposed to being the most efficient.

It is important to note here that filtration EFFICIENCY is a precisely defined quantity. It is the percentage of particles which the filter will capture (in this case a mass percentage determined using ISO test dust).

Filters are usually designed based on a fixed efficiency value, and then the rest of the system is optimised to reduce pressure drop (and cost). Car manufacturers don't usually mind slightly more expensive filter elements, as they can pass the cost on to the customers.

As I said before, the "performance" filter media sacrifices efficiency for pressure drop.

Originally Posted by Neil P

At which point does "more clogged " become useless ?

When this pressure indicator says the filter needs to be replaced

These are fitted standard on trucks and isuzu landies. The only reason the aren't fitted to cars is because the companies want to sell more filters (i.e. by scheduled service not by waiting till the filter actually needs replacing). Fitting one of these and only replacing your filter when it needs it would probably work out cheaper than buying a cleanable filter.

A number of people here and elsewhere have reported elevated silica levels in their oil when they have switched to oiled foam or cotton type filters.