2003 7.3 losing a lot of oil. No leaks visible or drippings. Does anyone know were a quart of oil could be goining every 100 miles?  

try looking to see if its drippin from between the trans bellhousing and the motor. if it is then theres a little plug up behind the bellhouseing on the motor that is prone to leaking. allot of people get it confused with being a leaky rear main. my girl friends dad had the same problem with his. its a easy fix except for splittin the trans away. good luck  

I started the truck yesterday with clean cardboard underneath and let it run for about 30 minutes. No drips. The truck is also hard to start.I checked in the piping from turbo and found some oil. But did not seem to be as much as I loseing. How much oil do you lose with bad turbo seals?  

I pulled the fuel filter today. Filter bowl was full of oil. So I guess I need to replace injector O Rings. Is This hard to do? Thanks for any input.