I guess you could look around the turbo housing to see if there was any oil leaking out, I kind of doubt it though. The turbo most likely will work just fine with a blown oil seal so with that much oil loss I would agree with kerry.

Take the turbo off yourself or have a shop do it but make sure it's rebuilt by a place that specializes in turbos or you'll be dealing with it again sometime, there is a lot of balancing to do that needs to be done by a pro to be done right.

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1985 300D Turbo ~225k
2000 F350 (Powerstroke) 4X4, SWB, CC, SRW, 6spd ~148k
1999 International 4900, DT466e (250hp/660 ft/lbs), Allison MD3060 ~73k