I replaced breather box and continue to add about 1/2 quart oil every 400 miles. It seems to use a bit more when I go on long trips. If I go according to FAQ (1 qt every 2000) my 940T is doing pretty bad on oil consumption. Should I be concern or do I still have time before I repair the turbo. Which I am assuming the problem is coming from...

If the oil was passing through the turbo, you will see white smoke from the exhaust. If this is not the case, have you checked for leaks around the oil return from the turbo on the passenger side of the engine. You have to get underneath to see it. Also check the line entering around the oil filter.

Do you have significant loss at the filler cap or valve cover gasket?

No white smoke or lost from filler cap or valve cover gasket.

if the oil is going out of the front side of the turbo...no noticable white smoke (and im talking 3/4 ltr per 100 miles!)

check the turbo piping for oil...if there is more than a smear turbo is on the way...

only so many places oil can go:-

out of the turbo (either smoky exhasut or oil in the tubes)

past the rings ( do a compression test)

external leak (wash engine off with de-greaser, run - check)

a rear main leak can show underneath the car (underside soaked!)