97 Impreza outback - 5 speed manual -276,000 miles.

 

My wife and I took the car to El Dorado National Forest yesterday for a day trip of hiking/exploring. As we headed up into the mountains, the trans popped out of 4th gear twice. Behaved normally otherwise. On the way back down, I kept my hand on the shifter when in 4th and the next time it popped out of gear, it was quite forceable. About yanked the stick out of my hand.

 

The trans has always been just a little growly in lower gears, but I noticed it seemed louder than usual when we pulled over for a dinner stop. Checked the gear oil and it was low. Stopped at a walmart and topped it off. A little quieter again, but here are the symptoms I can identify.

 

- A few days ago the speedo needle will occasionally wiggle. Reads the speed but wiggles at times.

 

- Considerable shift in the trans forward and backward. I notice this mostly in third gear. The stick pulls quite a bit when you accelerate.

 

- Kinda growly as it's been but a little louder.

 

- Pops out of 4th gear every once in a while. (I mostly skipped 4th gear on the drive home, but it's still working okay.)

 

- Feels just a little harder to shift into 4th.

 

I researched past threads to see if I could get a match. Similar I guess to

 

http://www.ultimatesubaru.org/forum/topic/135910-clutchtransmission-noise-97-obs-5mt/?hl=%20popping%20%20gear%20%20transmission

 

http://www.ultimatesubaru.org/forum/topic/80790-driveline-issue-with-98-impreza-outback-sport/?hl=%2Bpopping+%2Bgear+%2Btransmission&do=findComment&comment=674702

 

I did a visual check on the tranny mounts and the pitch rod stopper and it looks okay. I feel my first step is to figure out why the trans moves so much when I accelerate. Am I likely looking at the input shaft bearing? Any way to check and see?

With that kind of mileage.....I would suspect the internals are just getting a little worn.  Like you suggested I'd check to see why the trans is moving.  Try jacking up the trans a little bit to make sure the trans and engine mounts move with and they're not degraded.

 

The other thing to make mention, don't confuse the shifter linkage movement with actual transmission movement.

 

I've also got a 97 OBS and the trans is quite noisy as well.  I had tried a trans cocktail several years back and it has been more noisy ever since.  I've run Subaru's Xtra-S transmission in it and I think it helped a little bit, but is still quite noisy.  I've got just under 190k miles on it, and am just going to drive it until it craps out.  I don't have issues of the trans popping out of gear, but you also almost have another 100k on my trans.