I bought my GMC 2006 duramax diesel with the Allison transmission brand new. I needed a truck that size for my construction company. After 250000 miles just a few things went wrong, I was scared to take that vehicle to just anyone because it's a unique truck with special components. I've taken it to Kelly's auto repair twice and plan on taking it back again if something else breaks. They're very kind honest people They don't fit in with the world that we live in where everyone is so dishonest. Very knowledgeable!