Have a 2008 350 super duty van 6.8 v10, the streaming wheel is slightly off when driving straight down the highway. I am told by the dealer
I have to do a wheel alinement for a 190.00 dollars, am I hurting the tire ware by not doing an alinement?

 

There must have been some work done to the vehicle and it was not a complete job or the steering wheel would be in the correct place..
Not knowing just what was replaced it is difficult to say if driven in it;s present state.
If all suspension /steering parts were replaced, might only need alignment.You might be able to get an alignment somewhere else for less, check around.

 

Sometimes an incompetent technician doesn't center the steering wheel when aligning the front end. It doesn't mean the front end is out of alignment. If you have no abnormal tire wear, handling issues and the front end tracks straight without a pull, you may not need an alignment. Some people are just annoyed by an off center steering wheel.