When possible any repairs can be performed but not until completely diagnosed , leaks, solenoids, ect . All drivetrain repair such as universal joints, drive shafts, transfer cases, differential. The transfer case is part of a four-wheel-drive drivetrain system. The function of the transfer case is to engage and disengage the four-wheel-drive when activated and de-activated.
The transfer case is an aluminum or steel housing under the vehicle and the vast majority of transfer cases are either chain based or gear based.
Most 4-wheel drive vehicles have both a front and rear differential. The differential works with your transmission to deliver power from the engine to the axle that turns your wheels. The differential also makes turning your car possible.