Fuel filter micron rating - D12

Anyone know what it is?. Wanted to look at alternatives to the Volvo filter but want to be sure to get the right rating. Any thing lower than what Volvo spec will effect mpg.

i'm referring to the long life engine fuel filter not the water separator. Believe the part # 20976003

 

Thanks for input. I know what a micron is but appreciate the explanation. The micron rating of the filter will effect how quickly the fuel can flow through the filter. A 50 rating will pass fuel faster than a 2 rated filter. All the engines have a specified fuel flow rate, if you strict the flow of fuel too much it will effect the mpg. Most common mistake is to install an 'it will fit' filter in the Davco water separator glass bowl filter. The D12 engine requires a 25 micron filter in the Davco, install a 7 micron one and it will mess up your mpg.

I can find the rating for Donaldson, Fleetguard and Baldwin filters but can not find a rating for the Volvo OEM one. I guess I will buy all three and do a test. Although I have heard questionable reports on the Baldwin filters.

 

I just found a press release stating that in 2010 Donaldson won the Volvo 'best in class' premium supplier for filteration systems for Volvo Group 3P Organization, basically the commercial transportation division.

here's the release......

http://www.donaldson.com/en/engine/news/069852.html

It is possible that the filters are made to Volvo spec and the Donaldson branded filters are of a different design. There is a thread on this forum that asks the same question for cat engines. A cat test paper was linked and cat found that the Donaldson filters were the closest comparison to cat branded ones. It was also suggested that due to fuel flow rate tolerances it was advisable to stay with OEM branded ones but for oil filteration Donaldson was a credible alternative.