1988 Ford E150 - Loud

The engine is so loud with what I think is lifter noise, I have been told I could throw a rod. It just turned 102,500 miles and is a straight 4.9 liter. I drove over 3500 miles not knowing it had 5 grade Walmart synthetic oil in it when I had told them 3 times to use Valvoline 10-30. It was fine before that - healthy. Now I’m worried I could get hurt and don’t have the money to replace the engine. I’ve replace everything else but that. Am I in danger?

Did you mean they used 5-30 weight oil instead of 10-30?
These engines are tough engines, but some would have the exhaust manifold bolts loosen and back out. Any possibility this is the noise you are hearing?