Th 5 speed shuddering in low revs going up hill

[Muel]

Got myself a 09 falcon with the piece of **** 5 speed auto trans (was advertised as a 6 speed). Actually not as crap as it’s meant to be but it’s only done 85000. The only problem is when going up hill at in 4th or 5th the revs drop to mid 1000s and the car start to shudder all over. I can clear it by accelerating hard but it’s starting to give me the ****s as I drive up more hills than normal people. Guessing it’s a sign my box is starting to live up to its reputation. Anything I can do?