No, can't say I've ever noticed that.. but then my property still isn't fully whipped into shaped and I might not notice. /forums/images/graemlins/grin.gif
I have adjustable heights wheels on the back, and non-adjustable ones on the front.. with a couple rollers in the middle front. To get anything but a scalp cut I have to raise the mower a bit with the rockshaft before mowing. I wish the front wheels were adjustable, so I could just let the mower float.. as it is, because it's partially lifted all the time, it tends to float over depressions in the ground instead of following them. I can't back out over a ditch and have the mower cut down into the ditch unless I mess with the rockshaft constantly.
There were springs at one point on the front wheels to keep them straight, but they disappeared long ago.. and I didn't see the point replacing them since they aren't touching the ground anyway except when it's parked and detached.
Do your rear wheels rotate (change direction) easily? Maybe more grease back there? Mine spin freely, so the second they touch the ground they align themselves properly as far as I can see.
HTH,
Bob