The fuel in the cylinders exploding
I think it's called an engine
your engine is loud because, the fan makes that noise
bearing
It is the alternator....
whst causes screeching sound when i turn the key in my car?
If the 1999 Suburban noise is a sort of loud banging noise, the problem could be that the engine have jumped time. Jumping time would cause the noise and jerking in the engine.
a broken rod or valve lifter
i have a very loud tapping noise in my BMW 318i e36 1993 engine. its extremly loud on start up then drops down to very loud when idling. the noise never goes away. I've had people say the engine was about to throw a piston, i need a new engine, etc what could it be and is it possible to fix?
When lighting strikes it causes a cavity or vacuum in the air the loud noise is caused by the vacuum collapsing. as an example popping a plastic bag cause the same effect.
Muffler
You have to locate the source of the noise then repost your findings.
Wheel bearing