EddieR46

I have a 1998 chevrolet silverado which I don't drive much anymore due to the rising cost of gas.I drive it basicly once a week to carry off trash.The truck had been running well up until the other day. I had to drive it to work because my work car had a flat.I got in it and it sounded like every lifter in it was tapping bad,after a little bit it quitened down a little then eventially it quit.I thought maybe the oil needed changing so I did that but I still had the lifters tapping and then after a while they quit.Can anyone help me with this problem .Do you think that some of the lifters are sticking or maybe the oil pump is week(oil pressure is where it has always been)I wuold appreciate any help anyone could give me.
Thanks Eddie