Originally Posted by shemoves
When it warms up over there, try a good synthetic 40 weight and see if that helps (I know that GC is almost a 40 weight) with wear. I almost exclusively use Red Line 10w40 in my STi. I tried GC once and greatly preferred the Red Line. Not saying you need to bump up to a really expensive oil like the RL, just see what a thick weight does. Also, the results from the Mobil Clean 7500 seem to have been the best, but it seems to be bit of a give and take between that and the GC. I do like the consistent results of the GC though.
I've been tempted to try a thicker weight, especially for the warmer months but haven't yet gone thicker than the GC. I've been trying to stick with readily available synthetic oils that I don't have to mail-order. I may give the Mobil 1 5W-40 a try for one 5,000 mile interval and see how it works out.
As far as the results from the Mobil Clean 7500, keep in mind that was a shorter 2,480 mile interval. But I agree, it did seem to perform pretty well ... all things considered.