A bad transmission. The sound is from metal grinding on eachother.
Your question is too broad. Expand on it a bit. When does it make the grinding nose, right after startup, after it's been running a hile, etc. where does the noise seem to originate from?
I would guess that it is the wheel bearing. is it a grumbling sound or an all out grinding? If it is or was a grumbling sound and has turned into a grinding it is probably the wheel bearing.
scraping sweeking grinding clicking sounds like something is grinding will be most apparent when turning
A lot of times the grinding sound that is heard when going over bumps is actually the car scraping the cement. If it is not a serious problem then the best thing to do would be to drive slow over the bumps.
if its a front wheel drive vehicle then it could be the axels
You most likely need new breaks and probably rotors
check your wheel bearings.
Don't ignore that kind of sound. Find out what is causing it and replace or repair the faulty part. A "grinding noise" can be caused by an alternator, water pump, idler pulley, heater fan motor, air pump or any of a long list of components, many of which can cause some serious problems if they seize or come apart.
No. grinding poverty would be debasing
main shaft bearing
Could be a bad wheel bearing.