Some people don't fill through the filler plug because they have to pump the gearbox oil into the gearbox as the filler plug facing the horizontal plane.

Still messy, esp when you still have the original intake box getting in the way. I've seen people do that without using a proper hose and end up wasting gearbox oil all over the floor. That's why some take the shortcut and fill from the breather valve. We all know that you can't overfill the gearbox if you use the filler valve on the side but I have seen many who has overfilled, including the topic starter (otherwise we wouldn't be discussing this topic, would we?). Had a friend whose mech overfilled his gearbox and as he drove up Genting he could smell gearbox oil all the way up. Upon inspection he found that it was so overfilled that it was coming out of the breather valve as he drove up.

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Added on February 13, 2012, 9:17 amActually, it is very easy but some still get confused over it. Fill through filler valve until it flows out if the gearbox has no dipstick. If the gearbox has a dipstick, then fill through dipstick hole and check with dipstick.

This post has been edited by sleepwalker: Feb 13 2012, 09:17 AM

My manual gearbox comes with dipstick and I fill manual transmission fluid through the dipstick tube as there is no fill plug bolt.

As for the EVO manual gearbox, as far as I can remember there is no dipstick except for the SST EVO X, which like most dual clutch systems, is not exactly a manual gearbox by definition.

You can consider that every Subaru Impreza from the very first GC8 model until now has dipstick. Like Huakenny said, ALL has dipstick and not just the Impreza WRX models. Even the standard roadcar 1.6 TS model non-turbo has dipstick on its manual gearbox. For Impreza WRX/STi, it is harder to spot the dipstick as it is hidden behind the top-mount intercooler which sits on top of the gearbox.

I drive a bugeye. My friend drives an 18 year old GC8 Impreza WRX and that has a dipstick too. Watch the video below at 0:10 you'd see the gearbox dipstick. Do note that the mech has removed the intercooler and the dipstick is in plain sight. Otherwise it would be blocked by the intercooler but still reachable from the sides.



This post has been edited by sleepwalker: Feb 16 2012, 12:44 AM

People who blows their engines and especially gearboxes just don't know how to drive a 4WD. The engine and gearbox is fine, the driver is not. All these issues usually points back to an over enthusiastic driver who launches too hard, don't obey rpm redlines and remove the built-in safety switches when installing aftermarket boost controllers. I'm already running at 150K km and still on the original clutch and no engine rebuilds. Another friend of mine reached 200k KM on his factory clutch. Most people under 30 can't reach 50K on their first clutch, so it's more of a driver issue than component.