Replacement Head I.D. for Ford 6.0L Diesel
Identifying a Ford 6.0L head by dowel size alone does not necessarily get you the correct replacement cylinder head. Ford/International has two casting numbers for their 6.0L head, the early 1843080C1 through C4 heads which all have 18mm dowel holes and use an 8mm mounting bolt for the rocker carrier, and the late model or “consolidated” cylinder head casting #1855613C1. It is the #613C1 that can cause confusion. This head comes from the factory with EITHER 18mm or 20mm dowel holes and a 10mm rocker arm carrier bolt. The aftermarket 20mm head is the ONLY replacement for this head. If your head is a #1855613CI casting with 18mm dowel holes, you must use a stepped 18mm to 20mm dowel (FelPro #ES72248) with the aftermarket 20mm head. Failure to use this dowel can result in severe damage to the engine.

Dave Sutton
Sterling Engine Parts
Minneapolis, MN
January, 2014