Not exactly a sledge unless backchat to the umpire counts, but Trueman is also credited with an exchange as follows (although it sounds so perfect it could be an urban legend...)
Trueman was absolutely all over a particular batsman one time, bowling fast and unplayable. He gets what he thinks is a plumb LBW, the umpire says not out, he gets what he thinks is a definite edge caught behind, the umpire says not out, he gets him to hit it up in the air to be caught and the umpire says a no ball. Trueman is naturally frustrated because he doesn’t think he’s getting the rub of the green against a batsman who is clearly all over the place against him. Next ball he comes in, definitely no hint of a no ball in where his feet land, perfect line and length, bowls him clean through and rips all his stumps out. Trueman doesn’t even appeal, just turns and walks back and mutters at the umpire as he goes “I nearly got the bastard that time, didn’t I?”