Stumped !
 

I can't find the specs for the Motorcraft FL-400S oil filter threads! Is it 3/4" X 16 or is it 18 X 1.5 mm? The Fram web site says the PH3600 (equivalent to FL400S) is 3/4" X 16 threads, but Truckperformance.com has Perma Cool oil filter relocation kits for the 2001 F150 and it says it uses 18 X 1.5 mm????

Does anyone know the filter thread size for sure? Do you have any links that show the thread specs.?
I'm totally out of ideas.

The FL-400S is made by Purolator Corp.

Maybe you can get some definative info. from them.

Good Luck... XLT_D

Thanks for the tip! The Pulolator web site didn't have the filter thread size, but I emailed them and they responded right away. The Purolator L20195 is the equivalent size as the FL-400S and the thread size is 3/4-16 UNC2B (just like FRAM states for it's PH3600).

Are you saying the relocation kit for a F-150 uses a FL-400S? That's only a 1/2 quart filter.

No, the relocation kit uses a PH8A, FL-1, etc. - the big, 1 qt. filter. I asked about the threads for the adapter that goes on the filter landing that takes the FL400s.