Which model LG pump, I ran them for years. No more.
Yes, they are noisy, relative to alot of other pumps. But not screaming loud noisy.
Yes, they heat up the water signifigantly more than alot of other external, fan/air cooled pumps.
I usually used duralube to lube mine (at your own risk, could harm the seals although I never had a problem). The 20 weight NON-detergent they suggest on the pump isnt too easy to find anymore. You cant really quiet the pump, you'd have to quiet the stand you have them in but to do that, you will probably increase the heat inside the stand which could add heat to the tank.
I stuck by LG for years. Had too many pump failures over the past 5 years and got tired of buying new ones.
I swapped out an LG that was running my return and another running my skimmer. Replaced with equivalent rated Pan World (Blueline, Corallife) pumps. Much quieter and my chiller literally ran 10 minutes less each cycle just with the pump swap.