Dick from Canada
I have an older  Corepower unit model 58370. The newer Generac oil filters will not work as they have a flat bottom that hits the lock nut on the engine , so it can not be tightened up. I have been buying the Generac tune up kit that comes complete with spark plug ,air  and oil filter.   I now have 4  unused air filters and plugs. The oil filter for this unit can not be bought alone from Generac. I have found several filters that will fit as they have a concave bottom that does not hit the lock nut. I do not like using parts that are not original equipment . Any thoughts on this ?
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Cobranut
If you can find the correct cross-referenced filter for the OEM filter, there should be no problem whatsoever using another quality brand filter.
It's very unlikely that Generac makes their own filters anyway.
It took a bit of research, but I found WIX and/or Baldwin part numbers for all the filters on my Kubota diesel mower, tractor, as well as my Protector series diesel genset.
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cookelec
The filter listed for your model is an 0H9039 which is available from Generac. You may also be able to get it from Ziller.
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Geoff Z
It is available and we can set up drop ship from Generac. We don't stock it.
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Dick from Canada
Good to hear that the filter can be bought without buying the whole kit . Will call the local dealer to get the details.  Have been getting the kit at Home Depot and they advised me that the filter is only available by buying the whole kit. Maybe they will sing a different tune  this time . 
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grsthegreat
Home Depot won’t be able to get just a filter. You can order it thru Ziller 
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