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No Oil in Oil Filter

I have a 1996 Ford Ranger, 3.0L V-6 Flex-fuel engine with 100,000 miles on it. When I went to change the oil and filter a couple days ago, there was only a little bit of oil in the filter (not full as I have seen on numerous cars I’ve changed over the last 35 years). The oil pressure gauge on the dash reads normally, and I have seen no other abnormalities with the engine (other than the oil looking dirtier than normal when I changed it), What can cause the oil filter not to be filtering the oil properly?

Thanks.

If this filter is mounted in a position that allows the oil to drain out (upright rather than horizontally), and the anti drain back valve in the filter is shot… You can get the filter specifics from a filter catalog at the auto parts store if you care to pursue it.

Thanks for the reply.
For more info: the filter is mounted upward - the top is about a 60 degree angle from totally upward (30 degree angle from horizontal), So, basically, when the engine is off, the filter should be almost full.
BTW, I currently have six vehicles with only one that has the filter in the “drain” position. All filters, except the noted one, normally have a reasonable amount of oil in the filter when I change the oil.

Hmm… I’ve never actually owned a car with an upward-pointing filter, but I can remember way back when I used to change other people’s oil that I always liked the cars that had the filter mounted that way because there was no mess taking the filter off. I always thought that’s why they designed them that way!

Somebody straighten me out if I’m wrong: oil enters filter in center; goes to bottom of filter (in your case); travels back up along sides of filter- inside filter obviously; then branches out through lubrication system- as long as engine is running. Turn off engine, oil pump stops. Check (one way) valve prevents oil from going in opposite direction as when engine is running, so if check valve is shot, (allowing 2-way

flow), could oil be siphoning its way through center hole and flowing backward toward pump? (Filter is well above crankcase oil level and pump pickup.) Diagnose this condition cheaply by buying good quality filter and see if symptom disappears. Good luck.

Your car is fine and you should give it no further thought.I had an 83 Camry with 255,000 miles on it thet had an upside-down filter that was dry when shut off for twenty minutes. I loved doing oil changes on that car.

If you want to verify proper oil flow, remove the filter and start the engine for a few seconds. Get ready to clean up a BIG mess!

The oil flows IN to the outside of the filter element and back into the engines oil galleries through the center fitting…

It may empty due to a siphon effect. Assuming you are getting proper readings from the oil pressure gauge and the dip stick shows normal, don’t worry.

The oil flow in the filter is inward on the outer holes, outward on the center. The antidrainback valve is inside and over the outer holes. You can see the rubber valve on a new or used filter. There is still some oil left inside the can of the filter on removal. If you cut open the can or punch a hole in the can you will get a cup or more of oil out if oil is truely flowing through the filter.

Yes, the oil does drain out of the filters on sitting but it is going into the oil gallery and probably dripping through the crankshaft main bearings. You may notice that the oil light (if you have it) or oil pressure gauge takes a little longer to go out or up when started after a long sit than right after a short stop and restart. That interval is the time it takes for the filter to refill and full oil pressure to come up.

I have been concerned about the longer time for oil pressure to come up on a cold start because of the lack of oil flow to the crankshaft bearings and valve train. Also, I have wondered how the air trapped above the oil outlet center pipe gets out. My thinking is that the oil pump brings up the flow until the flow through the filter element paper allows the center pipe to be covered. After that the trapped air would just be compressed and expel the oil from the filter on shutdown. I opine that if the filter were ever fully filled with oil, the oil could not drain back either direction unless air worked its way back up oil gallery or through the oil pump – very unlikely on a healthy engine. I have thought about extending the outlet pipe up to the top the the filter and seeing what happens. Another experiment would be to prefill the filter and rig a way to get the filter on without spilling the oil over everything. That would make filter changing more messy but get rid of the worrisome slow come up of oil pressure.

Let us know if you have any other thoughts; if you come up with other procedures; or if you propose other experiments.

Thanks again for the replies.
As I looked at the replies, I forgot to add that I have been changing oil in this vehicle for the last 40,000 miles of it’s life (10 changes since I change every 4,000 miles - oil & filter at each change). This is the first time in that sequence of changes that I have run into an almost-dry filter. In other words, I have always had leakage from the filter when I removed it (oil is always drained first before removing filter). Also, this vehicle has a factory plastic funnel that is attached below the filter so that when the filter is removed the oil will siphon thru the funnel to prevent, somewhat, messy spills. Given that Ford installed that funnel, I had always assumed that they expected leakage when the filter was replaced. Up till now, I haven’t been disappointed.
As for the low oil pressure indications, this vehicle has always had an immediate pressure reading on the gauge upon starting the engine. I have not observed any fluctuations that would indicate pressure problems. Of course, the gauge may not be accurate.

Ford gauges on newer vehicles are just an on/off deal. They don’t really measure pressure. The needle ALWAYS rests in the same spot regardless of pressure…

Only if the pressure is above 6 psi. If it is below 6 psi, the needle drops.

I just changed the oil in my 1999 dodge ram 5.2 318 and for the first time in 40 years of changing oil in cars ,i had this exact same thing happen no oil in the filter running down my arm ,actuallyt i turned it upside down and nothing came out .it was sitting for an hour and cooled off ,but i was seeing a red flag so i googled it and saw this conversation.amazing ,could it be a factory defect in the filter ? my first thought was trhe filter was not allowing oil to flow thru properly,but back syphon could be the answer.i have great oil pressure now ,but it wasnt bad before ,i did notice occasional valve clattering ,like a hot engine ,but my engine temp was fine .i hope thats all it was and i have no more trouble but im going to pay close attention to it for the time being.

I had cold lifter noise in my 2002 Chrysler minivan the went away after the filter filled up. I read a tip on the Chrysler Minivan forum (now Allpar) to use a motorcraft filter rather that rhe Mopar or Fram filters I had been using because the Motorcraft had a better anti-drainhback valve. It worked, no more noise.

There is a bypass valve for the oil filter. Some vehicles us a filter that has a built in bypass valve where on other vehicles the bypass valve is in the engine somewhere, usually in the filter adapter. If yours is the latter and the bypass valve stuck in the open position, oil may not get into the filter. Had this happen once on my Nissan Pick Up but it cleared itself on the next oil change and never did it again.