re:overheating

I have done my fan and added silicone oil, you have to take the fan off the fan splits in to two it is held together by about 6 or 8 bolts i cant exactly remember how many.
You clean all the old oil out. At toyota depending on where you live or radiators works as well sell this silicone oil it is used for toyota land cruisers as they had a fair amount of problems with there fans as well i live in Brisbane and it is readily avaliable.

Hope this helps
Peter