If you’ve never changed oil on a 04-07 WRX STi this guide will take your step by step through the oil change process. This guide should be applicable to most turbocharged Subaru cars throughout the years. Check at the end of the post for part numbers, oil, filters and tools needed to complete an oil change.
1.) Get you car on a hard, even, flat surface and get your car up on jack stands. I put mine up on 4 jack stands, so that later on when you are draining the oil, the car is already level and will drain properly.
Where to jack and put jack stands has been debated many times before.
2.) Once you get your car up on 4 jack stands, it is time to remove the brush guard. There are 5 bolts to remove and they are all 12mm.
3.) Now that you got your brush guard off its time to get under the car and start your oil change. You should take a second and locate the oil filter and the oil drain plug.
4.) If your engine is cool, go ahead and start it up and let it run for about 5 minutes. This helps with the oil change. The oil gets warm and drains much easier and quicker.
Step 1: Once the car is up on jack stands / a lift, you want to support the transmission and remove the rear cross member. You will need to remove it later anyway, it also makes it much easier to work without it in the way. I used a bottle jack and block of wood to support the tranny, but im sure a transmission jack would work much better if you have one.
This picture shows the cross member removed.
Step 2: Once the cross member is unbolted you will need to unplug the 02 sensor, and unclip its harness from the cross member. It is held by two plastic clips that can be pushed out of the holes in the member without much trouble.
Step 3: Remove the bolt from the lower rod, I believe it is a 14mm. The nut on the other side is attached to the bracket, so you don’t need a wrench on it. I found that ratcheting wrenches work best for most of these bolts.
The bolt that needs to be removed is the one going through the rubber bushing shown in the upper right of this picture.
Step 4: Now you can disconnect the reverse lockout cable. It is held in with a pin that can be pulled out with a pair of pliers. I stuck an Allen wrench through the cam as shown in the Cobb short shifter install when I removed it just in case. There is a washer on the lockout cable that may be stuck in the grease, you will want to take it off and set it aside so it doesn’t get lost. The lockout cable can be seen on the left side of the picture above. You can now move the lower rod down, and move the lockout cable out of the way.
Prior to the Legacy RS turbo, Subaru had never enjoyed the experience of distributing a genuine performance car. Of course, there had been the 4WD turbo RX and Vortex, but neither could crack 10 seconds for the 0-100km/h sprint – although they were very reliable. The RS was the gun version of the first Legacy series released in 1988 and discontinued in 1994. The RS (Rally Sport) model was aimed squarely at world rallying, with many of its components and concepts carried over to the dominating Impreza WRX.
The center Viscous LSD on the MT models initially starts out with a 50/50 torque split, front and rear, and will up the ratio towards the end with more traction. The manufacturer doesn’t give a final figure, so the max split is either 65/35, or could even venture as high as 95/5, since the A/T model has a different system that is marketed at a 65/35 maximum split. A higher ratio would explain some of the handling characteristics at the limit. The rear differential is also a Viscous LSD model.
The BC/BF is unique in having an Air – Water intercooler with a front mounted radiator for optimal cooling. The bonnet scoop only provides cooling to the turbo. While later model legacy’s have all used air to air intercoolers.