warp2diesel wrote:
VM chose to spec the 10 micron filter and with a lift pump installed, a 2 micron will work at the needed flow. I suspect VM compromised and went with the 10 micron to not require an additional lift pump for other applications the 2.8L is used in.
I am trying to find a filter that will spin on and have a way for the existing filter head and water in fuel sensor to be reused. One candidate used on Volvo, Deutz, and Fiat truck engines is being fazed out of production and being sold on clearance. My goal is to have a cost effective 2 micron spin on filter that will fit the existing head and use the existing WIF sensor. When I have it worked out and installed, I will post it as an option and only recommend it for those who have upgraded to a lift pump.
More likely, VM/Bosch gave the OEM's that choice, and DC opted for for the 10 micron/no pump to save money. I've heard a similar story related by a Bosch-trained tech at an area diesel shop, regarding the Duramax - Bosch told them they needed an X micron filter to protect the injection system, GM wanted a Y micron filter so their customers wouldn't become PO'd over frequent filter changes, they compromised and picked a Z micron filter in the middle of the range.
GM went to a 2 micron filter on later model Duramax trucks, still with a vacuum fuel system, and Duramax owners started experiencing the same problems - having to frequently bleed air out of the fuel system, stalling , no starts (especially in cold weather), misfiring, low power. And they came up with the same solution - adding even a low pressure lift pump virtually eliminated their ills.
Good luck on your filter search. I spent quite a bit of time a couple years ago doing the same thing, with the same idea in mind. If you can find one, more power to you. After we tumbled onto the Omega temp probe, I decided for my part that any further fiddling with the OEM filter head was, in the words of a recent political candidate, nothing but putting lipstick on a pig - that the best choice for my part was to start with a clean slate.