New "technique" problem

I have since switched back to full frame after using crop bodies for a while and I seem to have developed a weird problem: A lot of my photos are now slightly "tilted" on the full frame body. I have no idea what I am doing "wrong" (besides the obvious of canting the camera).
I've gone so far as checking my shoes, trying to figure out if something physically changed...etc. I am at a total loss.
This seems to happen in city shots, especially where there are no real parallel lines...and is some landscape shots.
When I go back to "crop" bodies, it seems "better".

40D to 5D and 1D Mk II to 1Ds MK III are the cameras in question

Anyone ever have this happen?

maybe your lense with tha body is heavier?

It happens to me on a crop body.
It is your shoes......


Nah!!! Couldn't resist. I could just picture you checking your shoes.

I haven't found a cure. I straighten later when it happens.

Your muscle memory regarding the relationship between your left and right hands when shooting is mentally calibrated to the old crop body. You'll get used to the new one eventually, but in the meantime, you have to make a conscious effort to use the AF points or finder edges to make sure the camera is being held vertical against some chosen reference points in the frame.

thanks for the help. I swear I was looking at my shoes, thinking am I lopsided or something?
Again great tips from a great community.

You might try a new focusing screen. I went with a D screen after I added the grip to my 40D -- saw the same type of problem.

Anyway, the screen helped me immensely!