This thread seems to have the Nikasil problem at heart
. It concerns the V8s I believe and is because of the sulfur in the fuel. In CA. this isn't a problem because of the fuel mixture. It eventually will rot out the motor causing the leakdown test to fail. BMW will replace motors out of the 100k mi. but I don't think very far out of 100k. Blocks were changed in 95(?) and on to Alusil which corrected the problem. Cars have gone almost 200k without the motors failing in various parts of the country.
For good information see David Cecil's
www.E38.org it is a MUST
Good luck!
