hey guys. i am brand new to this forum and don't know where to even post my problem. i have got no help on duramax forum and a friend suggested this forum. so i hope you guys can help. my truck is an 01 lb7. 74k on it. original injectors. past couple days i've been noticing a rattle at idle and to 1000 rpms. today it got way louder. but it only rattles from idle to about 1000rpms then it goes away completely. no diesel in oil. no smoke from exhaust. no check engine light. no loss of power. idle seems a bit rougher though. from my reading so far sounds like it could be the pilot injection. any thoughts? please help...