Anyone know how to activate the exhaust brake on these engines? I heard a couple theories and tried a couple different inconvenient proceedures, but seems I'm getting nothing...

Anyone know how to activate the exhaust brake on these engines? I heard a couple theories and tried a couple different inconvenient proceedures, but seems I'm getting nothing...

You need to be in tow/haul mode if I remember correctly from some videos I watched a while back.

Is basically the same as the grade braking that they have had for a while, except it will work a little better since the turbo can help keep some back pressure in the motor and slow it down.

The exhaust brake on the 6.6 works fantastically. It will actually slow the truck down when going down a hill, to the point of needing to get back on the throttle to maintain speed.

But I have read the brake feature in the 3.0 doesnt work nearly as well.