Excessive wear, or lack of oil.
Or both.
Generally lack of oil is what causes the excessive wear.
Engine tappets
Probably
will tires make noise if there choppy on inside
The tappets may need adjustment or replacement, due to wear.
when the engine weres down
You don't... Hydraulic tappets are fitted. If they make a tapping noise occasionally that goes away get used to it, or add hydraulic tappet cleaner additive to the engine oil after an oil change. If they constantly make the tapping noise it's time to get them checked out. Could be expensive!
Diesels are normally noisy anyway - are you sure it your valve tappets? If so, they could be out of adjustment. Take it to a shop and have them checked and adjusted.
Normally loose tappets will cause a ticking sound in the engine. Depending on if you have mechanical or hydraulic tappets you may need to have them replaced or simply adjusted.
Agressive tread, bad alignment
the steering wheel wont make the front wheels make noise as there is no generating source from the steering wheel. it will be the other way around.
Yes. they open their mouth and make a loud noise that causes vibrations.
yes you do have to set the tappets