sludge in turbo

[roost]

Hello I am interested in a 99 f-350 with a 7.3 and am anxious to buy one if not this truck . The individual let me take it in to ford to have it checked out before purchasing. It blew some white smoke but runs great once warm and is a very nice truck for a decent price$ 10,900 Canadian and has 270 000 kilometers about 168 000 mi. The ford mechanics at the dealer said it looks like an ok truck with the exeption of an exhaust leak on the turbo , and even worse they pulled the intake ? hose ? off the turbo and found some "sludge" in it , witch means i have blowby and they said to stay away from it uless i get a realy good deal. they however said the the motor runs realy good on the test drive. I Told this to a friend with an older 7.3 non turbo and he said that it sounds like the ford guys are trying to scare me away from it , these things are tough, they all smoke when cold and are not easy to kill . also if I do need to work on it this is one of the simpler ones out there. I heard of the oil cap test but is some blowby normal ? and does sluge in the turbo mean the motor is on its last leg or just that the turbo needs a service and cleen ? I feel sceptical , but also wonder how accurate they can be on estimating the life of such a beefy motor without doing even a comp. test? ANY avice to stay way or sounds normal would be greatly apreciated . thanks so much.