4x4ord wrote:
As I have already pointed out, my Ford will generate 18 psi boost at 3000 rpm while grade braking without a trailer in tow. My Peterbilt will generate much more boost than that. If a non turbo'ed engine is pumping 5 cfm through an exhaust brake and a turbo'ed engine of the same displacement pumps 10 cfm through its exhaust brake and if both are creating 20 psi back pressure then the turbo'ed engine will be doing twice the braking. I think it is highly unlikely that the Ram isn't using the turbo's potential to create boost to make their exhaust brake as effective as they can. As far as what your guage is displaying, it is possible that it is programmed to show either boost or braking depending on whether the engine is pulling or holding back.
But the braking system in your old year model of Ford is more like a half exhaust brake and half engine brake utilizing exhaust/intake valves instead of just the turbo. I believe the exhaust brake in your new truck may be different.
Super Duty - Exhaust Braking FunctionApples to oranges.