Like Shibby said, 3 are weak to fighting, but that shouldnt be a problem in the E4. ============
Just give Linoone some better moves and get rid of tackle and fury swipes.
Swampert shouldn't be a HM slave; it has power. Give it Surf and that should be the only HM it ever knows.
Mawlie is good, but you may want to give some variety in teh moveset. Having only Dark offense is not a good choice.
Exploud is good, just take out Howl and put in something like earthquake. It needs more offensive moves
Sableye, like Mawile, needs some move variety. Try shadow ball or psychic. (Take out knock off)
Hairyama is a killer pokemon, but you really haev no offensive moves (that are good). Take out whirlwind, knock off, smellingsalt, and belly drum. Go to the Move Tutor, and give Hairyama some real fighting moves, like cross chop, submission, strength. (even though that is normal, it is still the 2nd best HM attack)
Do that, level up the team, all of them, by about 5-10 levels each, and you will beat teh E4 pretty easily.