Didnt get a chance to drop the car out this weekend, but the more i drive it the more im thinking its diff and not struts. I bounced on the rear seats and rocked up and down on the rear sills to try get some movement on the struts and nothing not a sound and just rolling over ramps with no power produces no noise either, its only on and off power. So think thinking t=its not my struts. After some digging i found this
"This noise is caused at the engament point in the R180 diff (Plated type LSD). Everyone will have this noise at some point or another, if you drive your STi like it was built to be driven. This is common with a mechanical 1.5 way type LSD.
The sound is normal. There are of course those unique cases when someone will have broken something.
With time the thickness of the disks wear down. The engagement point (initial torque) on the rear diff becomes less sensative (has more slack) to throttle input and gives a loud engagement sound (like a dog box tranny) when it it does engage. This is suppose to happen.
If you have this sound and then all sudden it's gone and you don't feel any engagement. You have a serious problem.
It should occur during acceleration engagement and deceleration engagement. Most noticable at slower speeds because there are less noises occuring. Thats how a 1.5 way type diff works.
It is very possible that gear oil changes make a difference in some cases. With new clean fluid, the diff now "re-seats" with the total amount of oil and different viscosity (compared to the old oil). It's not a fix, just a small
change. Your will probably hear your diff again very soon.
I think it's a good idea to change your LSD oil often. Change it in spring before the first track day of the year and after the last one. Clean the chips on the magnet of the drain plug. That should give an idea of wear and tear on the LSD.
The rear LSD can be tuned for different initial torque. STi does have an overhaul kit for this very purpose. STi also makes a pressure ring set to further improve on the sesitivity of the LSD"
The yanks seem to think its very normal, but im surprised noone on here has been a victim. Ill drop it out to ciaran and look into the wheel nuts and servicing the diff.
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