04/gmc c6500 w/duramax oil in cooling system
 

72fj here i have a 04/gmc c6500 in my shop it has engine oil in cooling system oil cooler core is new replaced in june of last year,removed and pressure checked no leakage i am thinking it is in cyl head injector cups or a oil passage frome block to head any info on diagnostics would be app thank you 72fj.inline 6 cyl/izuzu duramax engine:humm: