Changing the Oil and Filter yesterday on my 08 F-250 6.4 and while cleaning the Oil Filter Cap I noticed written on the side of it....Wix-Do Not Reuse Cap..or something like that.
WTF.
Well I bought the truck pre owned about 6000 miles ago and had changed the oil and filter and other stuff as soon as I took ownership...I put a Motorcraft oil filter in the housing and did not even realize it had the "Wix do not reuse" cap on it. Did not even realize till this oil change yesterday...6000 miles like this. Will have to go to the Dealership today and purchase an OEM cap so I can use my Motorcraft Filter. I hope I did not hurt anything. Wondering how much unfiltered oil if any passed through the engine.
Have not noticed anything wrong lately but then again I did not notice the Wix cap on my first oil change either.
Since I'm 40 miles to the nearest dealer for a new OEM cap... I went in the wife's car down to local OReilly Auto Parts and got a Wix Filter with Cap and put it on till I get in to the dealer for new OEM cap.
Tell ya what I have noticed... But thought it was normal....Every time I started the truck after sitting a while or a cold start I would notice the "low oil pressure light would stay on for about a second. Now it does not light up at all when starting.
Like I said....Hope I did not hurt anything...Runs Great.

 

I would change it to the correct cap asap and drive on. I think the riddle of a low pressure on startup is solved though.

 

I didn't think you could seperator the wix cap and filter? Did you change the oil once already since buying the truck? How did you separate the filter from the cap?

 

I changed the oil only one time before and I just gave the Wix element a good tug and it came out of the cap but did not realize it was Wix....Dropped the new Motorcraft element onto the tree in the housing and screwed the cap down onto it thinking that was that.....Did this in low light and just didn't notice the element and cap were Wix. Hopefully I did not do any permanent damage. Does not seem like I did.

 

I think the only time I would be too worried, based upon what you have said, would be some extreme heavy towing.

 

They say if the adaptor in wix cap is removed it will have the same dimensions as the OEM, but I would trash the wix and buy a new OEM.

 

Ya.... There was no adapter in the cap. When I unscrewed the Wix cap to change the filter this time....the Motorcraft element I installed at the first oil change actually stayed in the housing and had not snapped into the Wix cap.
I would have probably just dropped another Motorcraft element in and screwed the cap down but that's when I noticed the "do not reuse" on the cap.
I went to a dealer today and bought an OEM cap and the Motorcraft element does snap nicely into the cap.
I will likely just install the OEM cap and filter and remove the Wix filter and cap tonite when I get home.

 

That kinda sucks to realize that Motorcraft filters haven't been used on your truck. Hopefully the previous owner just put the Wix in before he sold it or traded it in. Where/who did you purchase it from? If it wasn't a Ford dealer, they could have just thrown a Wix in there to save expenses on the resale.

 

Hey guys,bringing up an old thread here. But anyway I've been doing a little searching,is Wix a good brand of filter for the 6.4,I'm asking about oil and fuel filters.Thanks..Phil

 

The answer is NO, stick with the filter that was specifically designed and manufactured for the 6.0 and 6.4 navistar diesel, that's Racor. They make them for Motorcraft (FL-2016 or Fram (CH-9549) Stick with them and avoid potential problems from "will fit" aftermarket filters that must have changes in their design due to Racor patent rights.

 

There were some reports early on of people taking the cheap way out with WIX and starving the motor of oil. Do you want to do that?

 

Contrary to the popular thought on this site I have never had an issue with the Wix filter. Every one comes with a new cap and if you measure from where the cap will bottom out to the bottom of the filter compared to a motorcraft filter and cap there is no difference in length. I still keep the motorcraft cap and have used a MC filter from time to time. Only wix filter issue I have had is the air filters, had one trigger the filter minder in around 10K miles for some reason, fuel filters have all been fine along with the oil.

 

When I had my 6.0 liter Wix made a filter that was identical to the OEM one and it was just fine. The new Wix Filter with the included Cap has severeal issues. One that worries me the most is they use a glue inside the filter that can separate (melt) at high temperatures and contaminate your motor. Its just better to go with the one thats designed for the truck unfortunately. They arent that much different in price anyway.