Some time ago I replaced my transmission filter (H6 motor, 4EAT transmission) and drained and refilled the transmission fluid. Subaru Canada wants $44 CDN for this stupid tiny filter, so I checked at http://www.wixfilters.com and bought the suggested transmission filter (suggested by Wix). To me it looks just like an oil fiter - in fact it's spec'd as an oil filter for some cars.
Today I was at the Subaru stealership (buying a Scanguage II - very neat toy) and asked to see one of the transmission filters. One difference I noticed was what seemed to be a metal post type thing running up the middle of the filter - from the far end of the filter (the bypass valve I guess) almost to the mounting hole.
I was poking at it in curiousity (fairly hard I might add) when it collapsed down. I now noticed that the post thing was in fact a metal screen in tube form with a solid cap at the open end of the filter (this is what I was poking at), running from the bypass valve to the mounting hole. Just picture metal mesh screen rolled into a tube and capped at one end with a little dime sized piece of metal. The open end is attached at the far end of the filter - the bypass valve I'm guessing
My guess is it's there as a failsafe - if the filter goes into bypass, potentially some crud caught in the filter material could be washed out and introduced into the transmission. This screen filter will catch any of this.
The wix filter (which has the bypass valve at the mounting hole, not the far end, does not have this. I don't think any 'engine' oil filters have them either. However, with the wix filter having the bypass valve at the mounting hole, when the filter goes into bypass, the oil is diverted BEFORE passing the filter material - hopefully negating the need to have a screen to catch any crud that might wash out.
I've had the wix filter on for about 10000km now with no trouble. I refilled 3x with Valvoline Max-Life, but plan on replacing with synthetic (Amsoil likely). I may replace the filter again with the Subaru one just for peace of mind.
Any thoughts on what this metal screen is for? Do you think the Wix is OK to keep using?
Today I was at the Subaru stealership (buying a Scanguage II - very neat toy) and asked to see one of the transmission filters. One difference I noticed was what seemed to be a metal post type thing running up the middle of the filter - from the far end of the filter (the bypass valve I guess) almost to the mounting hole.
I was poking at it in curiousity (fairly hard I might add) when it collapsed down. I now noticed that the post thing was in fact a metal screen in tube form with a solid cap at the open end of the filter (this is what I was poking at), running from the bypass valve to the mounting hole. Just picture metal mesh screen rolled into a tube and capped at one end with a little dime sized piece of metal. The open end is attached at the far end of the filter - the bypass valve I'm guessing
My guess is it's there as a failsafe - if the filter goes into bypass, potentially some crud caught in the filter material could be washed out and introduced into the transmission. This screen filter will catch any of this.
The wix filter (which has the bypass valve at the mounting hole, not the far end, does not have this. I don't think any 'engine' oil filters have them either. However, with the wix filter having the bypass valve at the mounting hole, when the filter goes into bypass, the oil is diverted BEFORE passing the filter material - hopefully negating the need to have a screen to catch any crud that might wash out.
I've had the wix filter on for about 10000km now with no trouble. I refilled 3x with Valvoline Max-Life, but plan on replacing with synthetic (Amsoil likely). I may replace the filter again with the Subaru one just for peace of mind.
Any thoughts on what this metal screen is for? Do you think the Wix is OK to keep using?
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