it depends on what unit you are placed with,my first term i was with a cav unit with a tanker brigade so i repaired wheeled and tracks now i am with a engineer unit so i also repair a lot of equipment also
The 63B MOS is no longer classified as "Light wheeled vehicle mechanic." It is now "Wheeled vehicle mechanic." If you are a 63B you can expect to work on HMWWVs, HEMTTs, and 5 Tons (M939 series) in just about every unit you will ever be in. As ridge_runner1 stated no matter what type of unit you are in you will work on what they have. They are not going to let you sit in an office and play internet hearts while the 62B (Construction Equipment Mechanics) work on the equipment. You will be out there getting "Cross trained" to fix their stuff. Also learn whatever you can about generators there is never a 52D around when you need one and if you can fix them then you will be golden.