On a 2001 4d 2wd i am hearing a quiet roar (similar to if you run over the warning gouges on the side of the highway). My mechanic says its the bearings and the sooner I get it done the better.
My question is what can i expect on the bill?

As a secondary question: a second grinding noise near drivers feet which is RPM dependent and only if the A/C is on. Is that the compressor for the A/C?

 

If you're talking front wheel hub bearings with the ABS, they can be $100+ ea. plus installation. I found a pair on ebay for $125 +$30 shipping.
As for the AC it could be just the clutch & that could be a couple hundred to replace. Another option is finding a good used from a wrecker or rebuilt online. The only issue with that is they'll have to recover the refridgerant & replace it, but at least it'll all be new.

IMO anyway

 

I just had my left front hub replaced at dealer. It hurt but I paid $250 for the part and another $250 for labor. That fixed the groaning I heard at 30 mph and above.