I e-mailed John Mears, head PPL Tech and here's what he said:
Some of the updates for 2014 -
I was hoping to have posted on the website, but no luck from last week.
2.6 Diesel Trucks
MWE groove must be inside neck area where intake cover is measured @2.6”
Maximum of one P-pump, with only one plunger per cylinder.
Front brakes only.
Dual rear wheels only permitted.
We used removed some wording from the rear suspension, concerning (must use one working shock absorber per wheel.)
Ink still in the book (No air bags and blocked suspension is permitted)
Everything makes sense but I'm confused about the MWE because it sounds like most everyone would need a new cover so I asked John for clarification and rationale. His response:
"No, it keeps people from stretching the mew (sic) groove out from the face of the wheel…..feeding the larger portion of the turbo…."
I feel like I'm missing something.....