Mechanic Job in St. Clair Shores, Michigan

Installed new radiator last week in truck.Everything went well and no leaks.Pulled in driveway yesterday evening and its leaking trans fluid from the fitting on the radiator or line not sure.drove truck for a week without any issues and all of a sudden its starting to leak.would like some help to resolve the problem.may b a new fitting or line..... not sure..... anyways trucks just sitting until looked at and fixed.dont want to take any chances driving it with this issue.better to b safe then sorry.Get with me asap would like truck fixed and on the road.thanks