Joined
·
401 Posts
how can I tell the difference between the two? my 351m in my 79 F100 is making a knocking/rattling noise at about 50+ mph. i dont have a tach. so ill have to estimate it at 2000+ rpm or so. oil preassure is ok by the factory guage (always in normal range), a little on the low side when at normal operating temp and high when cold. when cold, the engine makes less noise and im able to cruise a little bit faster with out getting the noise. it seems lately though im able to go almost 60 mph without hearing it. let me know if yall have any ideas or similar experiences. thanks.