1997 Ford "F53 Stripped Chassis" Class A Motorhome with a 460 (7.5L) V8. The manual says to use FL1A in one place and FL1HP in another. CSK website actually lists the F53 Stripped Chassis (many parts stores don't) and says to get FL1HP, but also says can use Fram PH8A. Now I know PH8A is a FL1A.
My 1990 Cutaway E350 Class C motorhome had the same engine and took FL1A (said FL1HP for severe service) and I always ran FL1A cross ref. Now the Class A motorhome gets no more oil pressure than the Class C did (actually it gets a tad less: 70 cold vs 75 cold on the Class C) and so I don't think the higher burst pressure of the HD filter is needed (Wix gives about double the burst for the FL1HD version than the FL1A version). Wix also shows nominal micron rating of around 29 for the FL1HP version vs around 19 0r 20 for the FL1A version. Do you think they just want the freer filter flow of the higher micron rating?
Confused? Am running a Maxlife FL1A version now. Can not bulging or anything.
My 1990 Cutaway E350 Class C motorhome had the same engine and took FL1A (said FL1HP for severe service) and I always ran FL1A cross ref. Now the Class A motorhome gets no more oil pressure than the Class C did (actually it gets a tad less: 70 cold vs 75 cold on the Class C) and so I don't think the higher burst pressure of the HD filter is needed (Wix gives about double the burst for the FL1HD version than the FL1A version). Wix also shows nominal micron rating of around 29 for the FL1HP version vs around 19 0r 20 for the FL1A version. Do you think they just want the freer filter flow of the higher micron rating?
Confused? Am running a Maxlife FL1A version now. Can not bulging or anything.