Well I have now about 7057 miles on a gm crate engine 290 horse 350 cid. And my question is this .... Is 1 quart of oil every 3000 miles acceptable? It seems that the engine should have broke in by now. The number 7 plug drivers side back has developed some deposits on it also, this motor is still under warreny so what should I do? the motor runs ok no miss / backfire etc. It has no leaks anywhere it must be burning it. Sure hate to take it out again. Thanks for the imput guys!!!!