excessive noise at 2000 RPM and above

It can be any number of things, Engine, transmission, wheel bearings, tire noise, etc. Have a mechanic go for a ride with you.

Does it do it in park when you rev the engine ?

First, check engine oil level. Isolate problem so u can narrow down the problem. If it always does it weather is in park or while moving, have a mechanic look at it in case it's a bearing rod and you'll damage it even worse.

Check the exhaust flow through the catalitic converter. It may be plugged and not allowing the exhaust to flow.