BigCountryx
1/2 ton status
K&n
thfonz98 said:supertech, from walmart, made by champion labs(whcih makes many of the other filters too)...was better then average in terms of flow, surface area, filtering as i remember reading AND at the low low walmart price.
i forgot to get one last time i changed my oil and am using an acdelco one right now though.
btw go lookup a fram 1991 k5 blazer filter...it will give you the wrong one(the one listed for '90 is right)...it give a much smaller(width and length) filter for 91...ive been down that road before i was informed how frams were the orange cans of death. only the tough guard is any good and its too expensive for how bad/good it is.
What Not To Use: Bosch, STP, and Wal-Mart Supertech
While both the STP and the Bosch filters were at one point good filters, they are now manufactured off shore of sub-standard parts. The filter assemblies tended not to have even pleats and generally less media than other comparable filters. There was also a complete lack of a well functioning by-pass valve. With most filters there is an obvious and discrete by-pass valve, but with these filters the can spring and the by-pass valve are the same. The real issue is that in order for the filter to properly by-pass the entire filter assembly would have to move down during use. That is actually not possible with filter assembly properly seating into the anti-drain back valve. This means that the by-pass will effectively never work. In the center of the of picture below you see the filter assembly (top) and the can spring/by-pass valve (bottom). (The can spring / by-pass valve would flip over and into the filter assembly.)
and they changed the number from PF30 to PF1218 or something on the 305 one??--why,after 30+ years,they had to change the number,makes no sense to me
Lets see here, the air filters allow more air flow at the toss up of allowing more dust through. So based on that you would want more oil flow with less filtering over a reduced flow rate with clean oilaldrichg9 said:Been using K & N
I like the hex nut on the bottom.
I've not cut one apart yet but so far
I just figured - good air filters = good oil filters.
maybe pretty stupid on my part but it hasn't bit me yet![]()
One of these days I will get the relocater mounted. 
They were a great filter for 2 bucks.


I've been told the "anti-drainback" valve is only needed for engines that have the oil filter located in a horizontal plane

(gallon) Too bad they only had 7! 