Im new to the world of stock fuel filters seeing I cut my bracket off my old truck and used it to hold isolator about 12 years ago lol. I was about to remove this one when someone on here told me in kind words that that was dumb  So what brand seems to be the best? 

The 33585XE is the Wix 7um filter, but when you look at the specs it’s 7um nominal. It’s a 8um absolute filter. 
 

That’s the kind of false advertising Wix does on diesel fuel filters and it’s ridiculous, IMO. It’s the same filter they have for the CR 5.9’s, which require a 7um absolute filter… not that they have warranties anymore, but the wix filter didn’t meet the min spec for warranty, but eluded to it with their nominal rating. 
 

Anyhow, thats my Wix rant. On a 2nd Gen the 8um is plenty of filtration. That being said the Baldwin PF7977 is the best filter for the stock housing. 5um absolute with better than OEM f/w separation and dirt holding capabilities. 

This is why the double stacking of the AirDog filter which is 3um and the the NAPA/Wix filter which does show a 7um rating. Regardless that 7um filter picks up a lot that the 3um doesn't. Last filter change the stock filter was nearly plugged tight and dropping fuel pressure. Pulled it out and the filter was black. Mark my renter picked up the old black filter blew on the hole and the black fuel ran out of it. I consider it a good filter when both the AirDog and stock filters go 50k to 60k miles before change. I admit I went way too long this time and the stock filter plugged up.

What are you running on the AD?

Donaldson, Fleetguard or the AirDog filter... I think the current one is Donaldson from @dieselautopower...

 

Edited June 30, 20222 yr by Mopar1973Man

25 minutes ago, Mopar1973Man said:

Donaldson, Fleetguard or the AirDog filter... I think the current one is Donaldson from @dieselautopower...

 

Dozens of filters that could fit… what part number? 

4 hours ago, Mopar1973Man said:

This is why the double stacking of the AirDog filter which is 3um and the the NAPA/Wix filter which does show a 7um rating. Regardless that 7um filter picks up a lot that the 3um doesn't. Last filter change the stock filter was nearly plugged tight and dropping fuel pressure. Pulled it out and the filter was black. Mark my renter picked up the old black filter blew on the hole and the black fuel ran out of it. I consider it a good filter when both the AirDog and stock filters go 50k to 60k miles before change. I admit I went way too long this time and the stock filter plugged up.

I've read this before from you and while I understand filtering (I think), if I'm reading this correctly, you have a 3um filter first, then a 7um filter second. So theoretically, the 3um filter should only pass 1,2 and possibly 3um particles through it. Everything larger should be trapped in the 3um filter. The 7um filter downstream would only be catching the particles that passed through the smaller filter just by chance. As the particles would be small enough to pass through the filter media except some get caught in the media by chance contact.

If you are seeing a significant amount of capture in the 7um filter, why not run 3um in both?

Also, do you run the same filtration all year?

 

Keep in mind a 3um filter will filter out a red blood cells but a 7um will filter out a white blood cell regardless very very small particles.