2004 Volvo EC240BLC - Swing drive filling with hydraulic oil and rumbles when stoppin

Hi all, Any help would be greatly appreciated. I purchased a 2004 Volvo EC240BLC. When I start to swing and when its coming to a stop when I bring the stick to neutral, the machine rumbles a bit. like a grinding sound. I went to check

the oil level in the swing motor and found the dip stick tube was filled to the top with oil full of air and cloudy white. I'm assuming this is hydraulic oil.



I'm thinking I will need to pull the swing motor out and replace the seals. Is this a complicated job that needs special equipment or can I buy the seals and change them myself.

Any info on where I can buy parts other than a Volvo dealer.



Thanks in advance