I got a big problem. I got an 88 Blazer 4.3. The oil pressure had been down around 20 psi at idle, then it was around 15 wile driving. It's been that way for months now. I put off and put off changing the oil, cause I never had time to change it. This motor is a remanufatured motor, bored 40 over I believe, but my father has been running 10w-40 in it since we got it. Well, since it was way over due for a change I ran some motor flush through it then drained it out, and the shavings that came out of it just shined like gold. I got a wild hair and decided to run 10w-30 along with some engine restorer to try to raise the oil pressure. I got it filled up, cranked it up, and the oil pressure needle was pegged at 0. At first I thought the sending unit may be bad, but when she started knocking home sweet home, I knew it was serious. I told my dad that I changed the oil type and he says you're never supposed to do that. He called our "other" mechanic and he thinks it's either the oil pump or the camshaft. I want to see what the gearheads have to say before we fork out the money to rplace these things. Robert
its ok to change oil weight but not mix brands you must dump old oil out completley and then it would be safe to change
