Engine(s): 12.5L. Regular service is always a crucial element in maintaining VGT turbos performance within standards. Some maintenance items to keep in mind are. Regular engine oil changes. Inspecting for air leaks in the intake system. Inspecting for exhaust leaks. Insuring proper aftertreatment system function. This is list of known model numbers. Just let us so the turbo is ready for you to be picked up. We will do our best to resolve the problem. Thank you for choosing us.