We had an F250 Econoline delivery van at a paving equipment dealership I used to work at. The 7.3L (??) diesel in that thing saw nothing but Delo SAE30 after the first drain and re-fill. It blew a head gasket at 330k miles or thereabouts.
When the heads were removed, the cylinders still showed the cross hatched hone pattern. Maybe more a function of the block material than the oil......
I think Delo is a great choice. Chevron just does not seem to market it as aggressively as Shell and Exxon/Mobil market their HDEO dino offerings...
And as for wear/engine protection, its always a solid choice.
I have a 97 F-250 hd 7.3l powerstroke 4oed with 3.55 screws with 230,000. i always use motorcraft filters so i am looking for a good oil and since it is summer i was thinkin a 30 wt flavor. i was wonderin which 30 would be the best? i was thinkin 250 hours, 6,000 miles on dino, 350 hours 10,000 miles on syn. that seem tolorable, i am running 85+% highway? does amsoil still have there hdd 30wt?
Under the SJ rating I recall the Zn levels being around 1100 PPM; am I correct to assume they did not change from the 2001 SJ standard to the 2004 SL standard ?
Also is it safe to assume that an HDEO 15W40 CJ-4 has approx 1200 ppm zn, only 100 ppm more than an HD30 SL ?