1 have a 35' Cafe Racer w/ TRS drives and transmissions. My starboard transmission started making a friction type noise when I was idling in nuetral. When I shifted to forward or reverse it went away. Checked dipstick and the Type F fluid was low. Added 1/4 quart to bring on dipstick. Noise went away. Ran 80 miles and noise came back and fluid was low. Where is it going?
Thx

Out the transmission oil cooler, or rear tail stock in the bellows.

How do I check for signs of either? Thx

Real good chance if it ran low on fluid the clutches are warped. Could be rear seal on tailstock leaking like rookie said or cooler . Pull drive look for fluid in bellow , take trans cooler and pressure test for leaks

where is trans cooler located?

not to hijack the thread.but are you supposed to use type -f fluid?my trans is slipping and has made the same noise.

Yes, type F.
From the conversations I had with my transmission guys they say type F is designed better for constant load.

thax rookie.....I am a real rookie when it comes to trs/trans.first boat with them

Not a TRS expert, but Type F fluid is known for lack of friction modifiers (ie DEXRON type fluids contain quite a bit vs F) faster shifts, better lockup etc at higher temps encountered in a racing application. Used quite a bit in drag racing transmissions.

Should be on your bell housing.