I have been Using the Fleetguard filters for years. But I know people who are of informed mechanical knowledge that prefer the Wix Filters.
Heres a little something I found when looking into the next generation of oil filters. There is a new filter technology that I was looking into. I dont know if Fleetguard is on this trail yet. But Wix is making a XD line of filter and it appears to be impressive. It features a bypass filtration element built into a full flow centrifuge process. They are claiming 50% better filtration over the standard line of filters. I'm not touting these filters at this time. But I will be doing some research on what others are finding.
Heres the source from what I pasted below.
http://www.wixconnect.com/assets/wixpne99-13.pdf
The Heavy Duty Filter
PRODUCT & ENGINEERING BULLETIN
WIX FILTRATION PRODUCTS DIVISION
HEAVY DUTY FILTERS
Wix Filters Built to Withstand
Cummins High Pressure
Surges
Wix Filters 51607 Oil Filter for Cummins
Series B Diesel Engine
Cummins has been
Experiencing Excessively High
Oil Pressure Surges with Their
Series B EnginesBuilt between
January and November 1998.
The Cummins B Engine has Pressure Surges in
Excess of 250 psi.
Some Filter Brands are experiencing Warping of
the Oil Filter Base Plate Assembly, Bloating
Filters, and Oil Leaks
Wix Filters 51607 has a Static Burst
Pressure of 350 psi and has the Design
Specifications to meet this kind of
Pressure #99-13 6-28-99 Wix HD
Good Luck
Don