I am not familiar with their knowledge on GM but w...

I am not familiar with their knowledge on GM but with Ford they showed nothing nor the willingness to satisfy the customer. The front man Terry is a flake. Do not trust anything he is saying as I witness him working other customers the way he worked me. I stayed 20 minutes in front of his counter 2 feet away and he did not noticed he has a customer. He was just working his texting.Pretty shamefully on Cunningham approach to customer satisfaction.
My personal experience is that they did not produce a workable tune which resulted in my engine failure.

After writing this review instead of fixing their bad work all Cunningham owner and employees wrote bad reviews on my company on line presents about services rendered by my company to them. They never had to deal with my company nor solicited services from it. All their complaints are fabrications. If this is their attitude toward business imagine the type of work they are going to do for you.
This company and its stuff is a danger to any customer and should not be in business.
They also wrote a response which is all lies. I wanted a working truck. They took the job. They were on the job for 1 day. They did not keep the appointment to fix the tune. They told me to try it and see how I like it. The truck broke.
I have no pleasure to start a feud with this type of dishonest people but also I hate the idea for them taking advantage of other people. They just wrote 4 false reviews on my company plus I witness first hand in their shop how bad Terry treats his other customers.