Some one had installed a after market oil cooler on the F150 I bought. It has 130000 miles. The cooler goes between the oil filter and the engine, it was leaking from the o-ring behind the cooler so I had my garage remove the cooler. Also replaced the timeing chain gasket and water pump at the same time. Now the engine has oil pressure issues, normal when starting up but near zero after it gets to temp. I put on a mechanical gage, it only reads arouund 10 psi when starting and zero when at temp. Befor the oil cooler removal there seemed to be no problems with the oil pressure. Where did my pressure go? Help please. Does the pressure at the oil filter read direct from the oil pump or does the condition of the bearings affect this reading?

 

Fram filter???

 

A mech oil pressure sensor reads the pressure inside motor oil passages, nothing too fancy. I'd swap filters and see. Also might consider dropping the pan to make sure nothing is getting caught in the pickup tube.

 

Thanks for the reply. I went and purchased a Motorcraft oil filter FL820S that this engine is supposeto take. I removed a Prime POF4459 filter that is smaller and the threads are smaller. I checked the Motorcraft web site and I bought the correct filter but it wont fit. Any ideas why the filter is not correct? Thanks

 

after market cooler ?

 

After marker cooler has been removed. I did a look up by VIN and it calls for a FL820S filter

 

Ater talking to a parts man we found a oil filter that fits. After changing the filter to a larger one I went from 10 PSI to 40 PSI at road speed and from zero to 20 PSI at idle. Thanks for the help

 

You need a FL1A filter. The FL-820S is for the 4.6L/5.4L engine, not your 5.8L.