Chryscar in Santo Domingo deals in all American brands. Their strength is Chrysler brands (Jeep, Dodge, Chrysler) with which they started, but couple of years ago they started working on other US brands as well. This is the best as an independent mechanic for US brands you can get in the DR, apart from the "casas" (dealers) which will charge you through the roof. Their "taller" is always packed with cars, and while you wait for a several hour job to be completed on your car, you see many people dropping vehicles or coming for checkups. That speaks of their quality.
These guys are professional, US trained and certified mechanics, work with "repair manuals" and not just by "having a look" and I have been so far very satisfied with their work. They charge more than a "street mechanic", but much less than a "casa" (dealer). They can also get a hold of parts for you, if necessary.
Tel. 809-599-5839
Rony (one of the owners) 809-886-8181 (cell).