I have a 2006 F350 King Ranch, Crewcab, SRW, Long Bed, My trailer is a 4 horse with a 9' LQ.  Loaded my trailer is about 16,000.  I live in Utah and come down some pretty good grades. 7-8% on a regular basis. I was having to use my brakes more than I wanted on some of those long grades. When you pass 3 run away truck lanes on one grade you know it's steep and long.  So I was worried about getting my brakes hot and of course brake wear.

I got the BD Performance Exhaust brake for my truck.  At the time ( and maybe still is) the only exhaust brake for a 6.0L powerstroke and automatic transmission. PacBrake makes one for the standard transmission. There are some other options for the 7.3L engine. The Powerstroke engine has the lowest exhaust braking of any of the big three diesels.  The BD Exhaust brake is set for 45 pounds of pressure before the back pressure valve opens, ( I think the dodge = 50 and Duramax =60)   This 45 pounds of back pressure produces 180 Hp of retarding horsepower. If you have ridden with a friend in a Durmax with an exhaust, the exhaust brake on the powerstroke won't seem as powerfull. But it works great and does the job. It's automatic.  Just have the Exhaust brake turned on and the tranny in Tow/Haul and the exhaust brake will engage whenever you take your foot off the fuel pedal. So you are either pouring fuel to the engine or braking, there is no coasting. If you want to coast, just flip the dash switch that turns the exhaust brake off.  It disengages under 25mph.  It works best in the 2000 -3000 rpm range. It doesn't seem to give me much braking un 1800 rpm.

Yesterday I came down I-80 in Parleys Canyon. Summit is 7200 ft, valley floor is 4400.  so it's a pretty good 20 mile downhill grade. A lot of 7% in the upper 5-6 miles.  I crested the summit at 60 mph and touched my brakes, The truck downshifted and held that gear all the way down the steeper grades.  I never had to apply the brakes at all.  I stayed in the 60-70 mph range all the way down. I've never had any valve float or over rev problems.

The downside:  When you turn on the BD Exhaust brake it turns off your cruise control. Can't have both of them on at the same time.  You need to engage the exhaust brake pretty much every time to drive the truck.  It's needs to cycle the valve a few times to keep the diesel soot from building up and binding the valve.  During the winter months when I didn't tow much, I forgot about this.  First trip this spring, No exhaust brake. I had to crawl under the truck with a wrench and manualy cycle the valve a few times to break it loose.  I just now remember to turn it on for a few minutes when I'm slowing  every day to get it to cycle a few times.  The other downside is the bolts that hold the brake into the exhaust system have a tendency to work loose. You need to periodically check them that they are tight.

The dealer who installed my installed a cheesy toggle switch on my dash. He could have easily used one of the empty Upfitter switches already built into the factory dash. He focuses more on Dodge trucks and wasn't educated about the Ford upfitter switches.