Re: what does "bullet proof" engine mean?
Yes, I believe that the term has mainly been used in reference to the 6.0 diesel, in as much as you can have "reliable" and "6.0" mentioned in the same sentence. There are several "kits" out there addressing the most common issues with the 6.0L, sometime referred to as "bullet proof" kits.
'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
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