Hello 7th gen fellows, I’ve been having an issue for about a couple of months with my 5th gear. months ago I took an 1200 mile road trip with no issues at all, on the way back about 1000 miles in I had my first 5th gear pop out and it scared tf out of me but I made it home. I changed my trans fluid right after and it honestly wasn’t low at all but it was sort of shiny. Months back home just commuting to work 5th was sometimes hard to enter and I’d either bang it in or it would enter somewhat smoothly. Today doing some freeway driving it started popping out again which it hasn’t done since the road trip but after about 5 seconds of driving in 5th it just pops out of gear, it was stay in 5th coasting but under acceleration it pops out. Any advice on this, Monday I’ll be changing my Trang fluid and suspected torn axle seal

 

You will need to remove the transmission, open it up and inspect the internals. This is a common symptom for a "low fluid" situation. You stated that the fluid level was fine, so it is likely that you have a synchro/slider failure that must be replaced (and likely along with the associated shift fork). While you are there, inspect all bearings and make sure all is well before re-assembly... this is the time to fix everything while the transmission is open.