Engine braking now vs then.

jbc28 wrote:

4x4ord wrote:
In 2009 I towed our 5ver over the Creston Salmo pass in BC with an 03 Duramax. I manually placed the truck in low gear and listened to the engine rev to over 5000 rpm as it struggled to hold back the gcvw of about 21000 lbs... about 35 mph. Second gear was a run away. In 2011 I went over the same pass with the same trailer using a 2011 Powerstroke. The engine was able to hold the trailer back in 2nd gear at about 3600 rpm and 45 mph. This year with 25000 lb gcvw my 2017 Powerstroke had no trouble what so ever maintaining 55 mph in 3rd gear at 2900 rpm. It was just a matter of setting the cruise and letting the automatic exhaust brake do its thing. There are a couple tighter bends in the road that prompted me to brake slightly to drop a few mph and then press resume on the cruise. The turbo boost would rise or fall depending on how much exhaust braking was required to maintain 55 mph. I was very impressed.

They do work well. If you were using cruise the service brakes may have been coming on too.

I noticed on the way back over the pass that the service brakes did come on a few times. When they come on the dash displays the amount of trailer braking being applied otherwise you"d be oblivious to the fact that the service brakes came on ... it is very smooth and it is possible they came on the first time over and I missed it.