My 2006 granite with a 370 410 maxidine motor has been pushing turbo boost pressure into the return oil line on turbo then causing oil to be pushed out blow by tube which makes a huge mess down the side of truck. I have put two Mack remanufactured turbo on truck, then went to a local rebuilder for the third one. The truck now will occasionally does the dirty boost failure once and awhile. It seems to do it under long heavy pulls under max boost. I did have the cam changed early in its life to a non emission cam because this engine out of factory was a dog at low rpm. Cam change fixed that problem. Not sure if this is contributing to this turbo oil seal problem. Has anyone experienced this problem?
