420SEL Pulling to the right

[Doug41]

I put on Arctic Alpin snow tires this year, and I notice that on the open highway which has a tilt toward the center of the road for drainage, that I have to steer "into" the upgrade slightly to stay straight. Is this due to these tires, or am I due for an alignment. The car seems to go straight at slower speeds and on normal roads....didn't notice it with the regular tires, but the car could have gone out of alignmnt since then...ideas?

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