The only place I've ever heard of that works on T1N Sprinters near me is Stoops in Indianapolis. However the posts (here and elsewhere) are all years old. The rreviews on Google recently look pretty bad. One of the reviews mentions the business was sold two years ago and since then, the quality has gone down and turnover of employees gone up. Don't know if any of this is true but I'd sure like to know of a knowledgeable and trustworthy mechanic in central Indiana.