Oil filter sizes

[Utah Willie]

For you gear heads out there. Does it make a difference if on a gasoline engine you put on an oil filter cartridge that fits just fine, threads, outlet holes and gasket, etc. , rather than the one called for in the books or manual?

 

[bulabula]

It would work. I don't have any qualitative info about putting a shorty filter in place of a longer filter that would possibly compromise long term filtering.

 

[C Schomer]

The bypass might be an issue. Like when Chevy went to spin-ons, they still had the bypass built in the base and none in the filter. F&D had the bypass in the filter and not in the base. Make sure there is a bypass somewhere for cold starts and high rpm demands. In the Olds diesel days I called a filter mfgr and found out, that dinky filter really was low in flow capacity but all mfgrs were rated 10 microns. Before that I had arguements with guys who said they just put more media in the smaller cans to make up the difference - BS! All the filters I've cut open lately had a bypass of some sort built in - some are just under the threads where you can see it and some are in the bottom of the can where you can't see it. If in doubt, the filter mfgr can steer you straight on what will be safe. Craig

 

[Loren]

Willie,



Yes, it might matter.



Most, if not all, oil filters have a built-in bypass to allow oil to flow to the engine if the filter becomes completely clogged. This bypass is set for a given pressure. If your engine requires a certain flow, and the filter is partially clogged, but the filter bypass hasn't opened yet because it hasn't reached its set pressure, you could starve your engine of oil. It may get some flow, but not enough to lubricate everything under the given conditions.



It's a bet.



Do you want to bet the price of a filter against the price of an engine that your non-approved filter will do the job?



The decision is yours.



Loren

 

[amsoilman]

Most, if not all, oil filters have a built-in bypass to allow oil to flow to the engine if the filter becomes completely clogged. This bypass is set for a given pressure. If your engine requires a certain flow, and the filter is partially clogged, but the filter bypass hasn't opened yet because it hasn't reached its set pressure, you could starve your engine of oil. It may get some flow, but not enough to lubricate everything under the given conditions.

VERY TRUE STATEMENT! Example: a Duramax Diesel oil filter has a "By-pass" valve that opens at 20 (PSID) Pounds per inch differential ,and the gas engines used in the chev's have the same filter size,diameter, and thread size, but the by-pass valve opens between 7-9 PSID!



Wayne

amsoilman