[alphatango]

Wasn't able to find a write-up for transmission oil change on a 2008 STi. Since the 2008's don't have a transmission dipstick, I was hoping someone could post a picture or explain where the fill plug is located. It looks like I will need to take the IC off but was hoping someone could verify. Thanks for the help.

[RayToday]

I'll try to help. I changed my gearbox fluid a few months ago. At 6,000 miles or so. The drain plug magnet had some serious metal sludge built up on it. I went with regular Motul Motyl Gear. I have about 2,000 miles with this oil and haven't had a problem. It shifts much better after the change.

Anyhow, I followed this existing forum how-to guide. http://www.iwsti.com/forums/how-inst...trans-oil.html (very helpful write-up imo)

The whole job only took a few hours. I got some big time satisfaction from doing this job for some reason. Well worth it.

I didn't jack-up my car though. I made 4 cheap and dirty ramps from some new 2''x10'' lumber. With the car up an extra 4'' I had enough room to work under her.

Some small things.

- Warm up the fluid a bit

- IIRC, you will need a #50 Torx to drain the clutch side, Not the 21mm that is shown in the guide

- It should be a 10mm allen for the filler plug shown in the first pic

- The part numbers for teh crush washers are not the same. 2008's use a different size. (I did not write down the new part number)

- Might as well flush some new fluid through while your doing the job

- You will need a long neck funnel, no way around it.

- I kept the IC on

- Gear oil didn't smell as bad as everyone says it does

Pics related...









Hope this clears things up.

[alphatango]

Thanks for the info. I actually went ahead and tackled the oil change yesterday. I initially thought the plug you have pictured was the fill plug pictured in the manual. But when another member said that fill plug is actually accessed from under the car and is on the left side of the tranny, the picture from the manual made sense. The worst part of it was filling the tranny back up. Spilled quite a bit and it took forever. That and waiting 2 hours for the oil to drain. Well worth it though. Ended up using Motul 300 and it definitely shifts better now.

[Bownse]

Nice write up except that it suggest using the torque wrench to undo the plugs. You should never use a torque wrench to undo fasteners. Save them for proper tightening. Use a breaker bar or a simple ratchet when undoing fasteners to avoid damaging your torque wrench. If you look at his tools, he's doing it right by using a breaker bar but he's calling it a torque bar. It's not since it has no torque gauge.

[GIXY2K]

Is there a reason to change the trans. oil so soon?

[slow_luke]

i changed mine after break in

[STI 08]

since theres no dip stick, how do you measure how much is in? just peer through the hole?

[kts262]

Originally Posted by STI 08

since theres no dip stick, how do you measure how much is in? just peer through the hole?

should be just like when you do the rear diff, fill it up until it starts coming out the hole you're putting it in. *yay accurate measuring!*

pretty lame i know, i wish they had left the dipstick like on the 04-07s...

[Nurek]

funny how in the 08MY manual, there are 2 diagrams for a dipstick. Turbo/non turbo engines. But yet on the 08MY there is no dipstick. :S

[STi413]

Sorry if I'm missing it and it was mentioned, but how much do you fill the tranny? In the past with my FWD cars you just fill it until it starts coming back out of the fill hole. Does that rule apply here as well?