This will be my 1st real off road...lol for me, adventure. I thought I would start at Shafer Trail and go to Potash and on to the cool bend on the Colorado river. Should I run 4W high or low coming down Shafer and should I air down and how much? Ford F250 with a Bundutec Camper. So much to learn. Finally getting my trip to the Canyons!
Is your Ford a diesel, and is your transmission an auto or manual? If a diesel, your engine braking will be stronger, especially if equipped with an engine brake. If your transmission is automatic, you can still keep it in the lower gears.
From a quick search, I find that the road is maintained gravel. I see no need for airing down. If your tires are not LT rated, or do not have 3-ply sidewalls, I would not recommend airing down due to potential sidewall damage.
That road looks scary at first glance. Let me tell what I would do, based on my decades of experience:
* Use 4WD Low for descending. Keep your transmission in whatever gear that allows for engine braking at whatever speed you feel comfortable with. Shift up or down as needed so that riding the brakes is not necessary. That descent looks to be very long given the large number of very tightly wound switchbacks. With the weight you are carrying, you don’t want to be over heating your brakes. If you’re lucky enough to come to a safe stop after your brakes fade, it takes a very long time for drums/rotors to cool enough to proceed.
* Going back up, I also recommend low range. Every 4WD vehicle I’ve owned is/was easier to climb winding and switchbacked roads in low range. In high range I found myself having to constantly shift - or my automatic transmission ceaselessly changing gears - to keep the engine in the powerband. Low range greatly reduces the need for shifting. You and your truck will be happier. Every truck I’ve owned allowed comfortable cruising at 25-30 mph in drive or 5th gear at no more than 3,000 RPM.
As for those who feel that 4WD is not necessary unless needed, I disagree. I run in 4WD even on maintained dirt roads. Not because it is needed, but to keep all shifting and front end parts moving and spinning frequently, limber and lubed. Because if you don’t use it, you just may find things seized and unavailable when you do need it. I’ve seen that happen numerous times to others who were stuck, shifted into 4WD and only the rear wheels spinning. The manual on my 4Runner instructs to drive several miles monthly in 4WD for that reason. I’ve put on more than 200,000 miles on my vehicles without drivetrain issues likely for that reason.
Have a great trip!