June Shannon, Honey Boo Boo and the rest of the clan got an enormous salary raise from TLC after the second episode and they didn't even ask for it ... TMZ has learned.

Sources very familiar with the situation tell us ... the family received between $5,000 and $7,000 an episode at the beginning of the series. We're told after the second episode it was apparent to TLC they had a big hit on their hands, so network honchos approached the family and told them they were boosting their salary. Our sources would not be specific ... but they say the increase gave them somewhere between $15,000 and $20,000 an episode.

We're also told TLC volunteered to cover various expenses, including a bodyguard/driver for Sugar Bear, who was incapacitated after his ATV accident.

And there's more.  We're told TLC even offered to help the family find a somewhat larger, more secure home, but June refused.  She said she wanted to stay in the house because she makes a big deal over Christmas -- decorating the house for the community.  June is heavily involved in her town.

Read more here.