Ok so I've looked up the wix 42790 &fleetguard ,Napa gold...actually called & all of the dimensions are the same but when it comes to what says biggest od on all the filters they say 10.5 but all of the jobbers say there 8.5.Everything else is the same.If I order today the part store will have it tomorrow. But I have to pay ahead of time.So I want to make sure I'm getting the right one. If not I will just order from pure diesel. I would just rather have it tomorrow.So what's going on? There all the same part #.I thank you in advance.

 

I'd bet 10.5...OD

 

I just measured mine and it is 10.5 OD.

 

If you buy from Napa, tell them you are in the American Trucking Association and you can get filters half price.

 

But why is napa & the wix one all have the same other sizes but it says 8.5 od they even showed me on the computer

 

I do not know, my current one is a wix, I've had fleet guard, and even the cat filters in the past, and they were the same size as my current wix.

 

I bought mine in 07. Still going strong...