I have an lx178 that doesn't cut very evenly. I have replaced the blades and nothing else appears to be out of place. Any ideas?
If you installed new blades then the deck almost has to need leveling. The hangers/linkage could be bent or out of adjustment.
I would think the deck is too high in the front for whatever reason.
What height number are you using to mow?
Take the deck off and with it upside down check all the blades but unless something is
really screwed up with the spindle(s) it almost had to be the deck hanger(s).
Does the height adjustment and lift all work normal? Smooth/easy/both sides equal?
The seat/shell is easy to remove and then you can better see the linkages and what they do...
The LX178 was made with 48", 44" or the 2 blade 38" like mac has.
Looking at the grass, how high do you think the hump is? 1/4"?, 1"?
This is indeed more strange if you have only two blades.