Sorry for so many posts. I am reading things and they are prompting questions. According to the info I read, special engine oil needs to be used to avoid aeration. Read this article about engine oil.
"The most common problem with Ford's 7.3 Direct Injection Turbo diesel is related to engine oil change interval and type of oil being used. It is critical for proper engine operation that the customer or technician servicing the vehicle check that the correct oil is being used. This engine uses a high pressure oil pump to operate the fuel injectors. Typical system pressures are 500 psi at idle, 1200 at 3300 rpm in neutral, and 3600 psi at full load acceleration. Oil for the PowerStroke requires an anti-foaming agent to prevent the oil from aerating, which would result in poor fuel injector spray patterns and reduced power. Depending on vehicle usage, the anti-foaming agents are depleted in 3000-5000 miles.
The only oil recommended for the PowerStroke by Ford is Motorcraft Super Duty 15W40, 10W30. Each of these has the proper additives in them for use in a diesel engine including the anti-foaming agents. The 15W40 is recommended for normal climates, the 10W30 for temperatures below 20 degrees fahranheit. For temperatures below -10 degees, 5W-30 is recommended. There are other oils, however, that do meet all the requirments for use in the PowerStroke. The specifications the owner needs to look for on the label are the API rating of CF-4/SH or CG-4/SH or higher. Some other oils with the correct"
I hope I am helping and not causing more problems.
Tuesday, October 1st, 2013 AT 6:36 PM