The other day, I towed a relatively light load of around 5,000 pounds.

I live in Washington state, so we have many steep hills to climb and descend around here.

With the tow-haul mode on and the auto exhaust brake, I didn't appear to be getting any actual exhaust braking while descending the hills or slowing down.

While going down a hill, the exhaust brake usually kicks on to keep the truck at the desired speed I set.

To maintain speed, the truck uses a combination of down-shifting and kicking the brake on.

Well, this whole 600-mile trip, the truck would downshift but not kick the exhaust brake on.

The exhaust brake on the gauge would indicate a small amount of exhaust brake pressure, but it was either so minimal it didn't have any effect, or it was lying.

I couldn't feel it working like it usually does.

A little background on the truck. 2015 6.7 with 92,000 miles and I deleted and tuned a year ago with the DRD tunes.

Currently have the P00AF code for turbocharger boost control module performance.

Im aware Im going to need a new turbo/actuator soon, but on this trip, I didn't have any turbo issues.

After reading what other people say about that code, I should be losing turbo and exhaust brake performance.

The turbo worked fine the whole trip.

The question is: would I start losing exhaust brake performance without losing turbo performance?

The turbo was usually operating the whole trip and the exhaust brake was not.

I already have a plan on the horizon to buy a new turbo actuator from City Diesel.

I also looked up my VIN, which is part of the select few 2015 trucks' extended warranty group for the turbo actuators—hoping to get reimbursed when I purchase a new actuator.

Any thoughts would help.

Thanks