I just got a 06 wrx with no mods at all and 30,000 miles on it. Im not sure how the guy before me treated the car but it seems to be in pretty good condition. When im shifting from 3rd into 4th above about 3000rpms I get a grinding noise . It still shifts into 4th fine. I was thinking it was a sycro going out because I had a similar issue with 1st gear in my bugeye and their was metal shavings in the tranny fluid. When I changed the tranny fluid in my 06 there was no sign of shavings at all. What else could it be???????????/
It could also be lazy shifting - it happens - are you sure you're pushing the clutch in all the way, shifting quickly/smoothly, and giving everything enough time to engage before stomping the gas again?
I believe it's also been proven that Uncle Scotty's Cocktail becomes acidic after several thousand miles and that's a problem too. Be sure to do plenty of research before making a decision.
+1 to what John said. Search around on Uncle Scotty's. Its not that great after all. But it seems some still run it. Guess its a drivers preference and how often you want to change out the fluid.
USC has been proven bad, Blackstone Oil Analysis proved it. Don't use it.
Personally I have tried stock (whatever it came with from factory), Redline 75w90NS, Subaru Extra S, and Motul Gear 300 75w90. All were pretty good, but Motul Gear 300 is the best IMHO. I have been running the Motul for about 10,000 miles and it still amazes me how smooth the shifting is. For me it is just better than the rest and the only stuff I will use for now on.
Also, my tranny has about 80K miles on it (20K of which have been since my hybrid build pushing 320whp/294wtq). My tranny is still running strong, no grinding, and I have yet to see shavings when I drain the fluid. Maybe I am just lucky (knock on wood, LOL).
I love the Redline Heavy Shockproof gear oil. There's a new cocktail out right now that sounds better than the USC. It's Motul 300 with two other additives. I'll have to look up the additives.
I am weary of mixing different oils. Particularly non synthetic w/synthetic. Who knows if when you mix these oils if they actually combine properly and don't separate. Each oil has it's own properties/ingredients/additives and sometimes things just don't go well together and could break down. I don't think your transmission is a good place for a science experiment.
However, I have heard Andrewtech (a well known/trusted subaru transmission guru/builder) recommend Motul Gear 300 with some Redline Shockproof and they say it is great. I say just use Motul Gear 300 and be done with it, b/c it works very well.
I've also heard it's good. I'm using straight Redline 75W90 NS in my trans and 75W90 in my rear diff for now, but I might switch to that the next time around.
my 2004 wrx does the same thing. now i have to shift it so nice and perfectly for it not to grind from 3rd to 4th... just changed the fluid too and it was from the dealer. hope my trans isnt going to go..
take it back....i bought my 06 with 36xxx bone stock and it was doing the same thing, i took it back to the dealer the 2nd day i got it and they replaced the syncros it fixed the problem but two months late the trans gave out and i paid $800. 4 months later 5th gear got stuck dealer paid and i saved $1200, 2 months later the trans gave out in LA 300miles from home i saved $750 because i have AAA road assistance but i was F**kin pissed man. they dealer said i abused my car and they refused to warranty it at 45xxxmiles because i had a spt intake and spt cat back exhaust so i paid $1200...F**K RANCHO GRANDE MOTORS,,. but 2 months later i saved some money and i got my trans built W/ACT stage 2 clutch and wheel and i love it. its unbreakable...TAKE IT BACK IF U CAN MAN IT WILL SAVE U MONEY, HEADACHES, HAIR LOL, TIME
When you say, had your trans rebuilt, do you mean with stock gears again? If so, a grippier clutch usually isnt advised. The grabbier clutch puts even more stress on the transmission, instead of letting the clutch burn or slip taking the brunt of the "heavy or hard" driving.
Transmissions usually don't just break, although there are some occasions where manufacturing defects are to blame. Most of the time, parts fail due to some type of abuse - banging through the gears, not pushing the clutch in all the way when shifting, applying the gas before you're in the next gear, modifying your power far beyond stock... just saying.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Subaru WRX Forum
329.6K posts
38.3K members
Since 2002
We're a forum community dedicated to the Subaru WRX. Come join the discussion on performance modifications, accessories, turbo upgrades, maintenance and more!