Has anyone installed an aftermarket inline fluid filter on a 4l80e? I have heard that this will not work as it causes a pressure drop in the fluid across the filter and messes up tranny operation.

I did one on a 700R4 and it caused a pressure drop. Removed it and sent it back.

SnowDrift

What were the symptoms snowdrift????

insufficient flow, which caused very low transmission oil pressure. I put this on a fresh built 700R4 and the tranny "tanked" at about 50-100 miles. Rebuilder stood behind it, although it may have been my fault for putting on this filter. He checked the pressure after the filter and told me it was way too low for him to be comfortable with it, so he removed it by the time I got it back. I trust this rebuilder's advice, so I didn't give it a second thought when he told me he may take it off if he didn't like what he saw.

The rear of the transmission was not lubricating well, so it failed. After removing the filter, I didn't have any more troubles and drove it for another couple years before I sold the truck to replace it with a heavier chassis.

Hope this helps

SnowDrift

Thanks for the reply snowdrift. I think I will just use synthetic and be diligent about keeping it fresh.

Inline filter only affects the cooler and lube. Fluid comes out of the torque converter ( fluid at its hottest temp) and goes into cooler then gets routed back to trans and is sprayed on the geartrain for lube. Inline filters will restrict very easy because of their design and should only be used after rebuild to catch old debris and then removed unless it is a full flow canister filter. This should not affect mainline pressure. If in fact the inline filter clogs up, usually we will have a torque converter clutch stuck on because of flow interference or burned up geartrain because of no lube spray. Hope this helps.
mike