HELP! Grinding gears....WTF?

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
I sort of expected the grinding to get worse at an excellerated rate. It just hasn't been any worse. Once again, I'm not permitted to do fluid changes in the parking lot of my condo, but when I move in with my gf in a few months, I'll have a garage. I'm glad you reminded me though, I am first going to try adding some Lucas Oil syn. tranny oil to see if that stops the grinding.

Ultimately, if fluid changes don't fix the grinding, I'm going to wait a year or more until I have the motor pulled and built. I'll pull the tranny and send it for a rebuild at that time. The parts are not too pricey, but labor costs are terrible.
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Furthermore, there really aren't any shops locally that will agree to do the work AND the ones that would do it, inspire ZERO confidence. One shop manager said: "What kind of car is this again? Subaru 6-speed? Nah, we don't do exotics."
 

Alin

Diehard Car Enthusiast!
Bump. What came of this?
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Nothing so far. I'm babying it for a while. I am still kicking around the idea of putting in the Grimmspeed Tranny Cocktail but I hate the idea of draining $70 of perfectly good AMSOIL. I recently added a small amount Lucas Oil tranny fix. It's a friction modifier similar to what you'd get with the cocktail. No change yet...maybe I didn't put enough in, but I didn't want to overfill it and damage the seals.
If I basically butterfly shift into 4th (though I still use the clutch) it doesn't realy grind. 5th is still hit or miss. Doubling clutching helps sometimes.
What is strange is how I can almost always avoid a grind, especially when downshifting into 4th. From 5th, I put the clutch in, shift into 3rd but don't let the clutch out and THEN go right to 4th, there is no grind.

Can anyone explain this? I have a very limited knowledge of whats going on inside the tranny. :lol:
 
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It sounds like a syncro issue.

TRE does STi transmissions.

Heres the link: http://www.teamrip.com/

He's currently doing my evo trans. He had an STi trans being rebuilt when I was there. They are located in K-zoo. They do amazing work.
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Awesome. Thanks for the heads up. That's gonna have to wait until I have a second car I guess.
 

zax

New member
FWIW, I'm not sure how the power output has anything to do with Synchro wear unless you are really banging gears.

Years ago my bugeye developed a nasty 4th-5th grind during every shift. I was using Redline 75w-90 gear oil at the time (nasty stuff; don't recommend it). Now, I don't fully recommend this, but it worked for me... I ran Uncle Scotty's Cocktail for 3000 miles. For those not in the know, USC is a nasty mixture of gear oil, synchromesh, and some other garbage. It's not recommended for Subarus, honestly. However, it did clear up the grind. I've been running Subaru Extra S for 60k miles in the bugeye and the grind never returned!
 

Batmobile_Engage

Squirrel Meat Aficionado.
Staff member
Hmmm...that's interesting. Idk about the bugeyes, but the '04's are known to have weak 4th-5th-6th gear synchros.
 
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