Frank,

Most have anti-drain back these days, but some valve designs are more
effective than others:

http://minimopar.knizefamily.net/oilfilterstudy.html

Interestingly, Canadian Tire Motomaster/Formula One filters are all
rebranded Frams. Same is true of Quaker State/Pennzoil. If you're buying
filters at Canadian Tire, get K&N. Elsewhere, try Carquest Premium (aka
NAPA Gold).

Even some Mopar filters are Frams in disguise:

http://minimopar.knizefamily.net/oil...udy-mopar.html

Steve
http://xjeep.dyndns.org


FrankW wrote:
> Well I wouldn't be surprised if the cheapest Crappy tire
> filter didn't have one. Actually someone told me that some don't.
> Didn't mention a brand though.
>
> Jerry Bransford wrote:
>
>> I haven't heard of any oil filter that doesn't have a check valve
>> Frank. Even the cheapest Fram filters have that.