Problem of fan noise

Yes, your fan sounds like the bearings are going. Its time to replace it.

But the bigger question here is are you pushing the system too far with so many VM's. I would strongly recommend you start monitoring the built-in fan & thermal sensors. I would get this tool as it one of the best out there: Temperature Gauge Pro. I suspect you maybe pushing your system too far here given its condition. Take a set of readings and then do the following and test again note the difference and let us know as well.

Since you'll be going in to replace the fan, maybe its time to do some deeper cleaning and rehabbing. I would start by getting a soft paint brush a couple of cans of can'd air so you can scrub the dust buildup and blow it away. You should pull the logic board and do the other side and you should clean off the old thermal paste and refresh it on the CPU, GPU and the controller chip using a high grade paste. Follow this IFIXIT guide: MacBook Pro 17" Models A1151 A1212 A1229 and A1261 Heat Sink Replacementand I would use this: Cleaner & Paste. Doing all of this should lower the running temp of your system.

The next thing I would do here is if you are running low in storage space think about replacing your HD. I would strongly recommend getting a Seagate SSHD unit as it will also add some zip with its deep SSD cache, and these newer drives run cooler as well.

Lastly, as the air is getting dryer with the seasonal changes its time to be more careful with ESD. Make sure to use a ESD mat and wrist strap that is correctly grounded. When you are going so deep into a system your chances of damaging something with ESD is much greater!