Re: Transmission ?
The vent you speak of is similar to ones found on differentials. The vent is just a fine filter on the end of a rubber tube. You should be able to find it easily enough. I'm not sure about the F series, but on my Dodge it goes up in front of the fire wall. Still, if you can get under the truck safely, check around toward the top (if you can see) for a rubber/hard line about 1/4" in diameter. There should be a small round 1/2" filter on the end. Nothing fancy, but it does the job to keep pressures on a proper level.
'11 Ram Quad Cab 4x4 SXT 5.7L HEMI (stock); 48,500m
'06 Pontiac G6 GT 3.5L 220hp; 64,000m
'12 Chrysler 200 Limited 3.6L 283hp; 28,000m
'99 Taurus 3.0L 2V Vulcan 145hp; 154,300m - Traded
Amsoil in all vehicles!