Not only have the cold temperatures made your car groan when you start it, but it has also caused vehicles to make more noise traveling along streets that are a bit bumpier than usual. Iowa Department of Transportation maintenance engineer, Bob Younie, says extreme temperature swings force surfaces to expand and contract more than normal — especially when it happens for a long stretch.

 
He says you can see the impact of the up and down temperatures all around us.

 
The D-O-T is responsible for taking care of 94 hundred miles of highways across the state. He says the problems will continue until Spring.