lenr wrote:
...I don't believe that Ford ever had an exhaust valve style brake; just vane control starting in 2011. I find that my 2012 works just fine in tow haul mode with cruse within 10 mph of the cruse setting. So just set it 10 mph less than what you want to max at as you crest the mountain. You do need to be able to watch the rpms run up toward 4000, but that is where red line is.
The 6.0 PSD used a VGT that was vacuum driven and did provide exhaust braking. It was not as effective as my new 6.7 CTD, but it worked well on my F250.