Ok last time i posted a thread i said that my truck was making a loud roaring/moaning noise at about 2,000 to 3,000 rpms and on up, I think that I have narrowed down the problem i talked to a retired mazda mechanic and he said that it could be a hydralic lifter that isnt pumping up like its supposed to!!! The pickup is still making the noise but it doesnt do it while idling!! has anyone had any problems with this? Is it hard and costly to fix and could it be done at home or do i need to get a mechanic to replace it?!!! please help!!!