Using 4wd to slow down
I was reading the last issue of trailer life, the article a couple wrote about looking for a new truck. In the article they said that when going down a step grade they will put their truck in 4wd low ...
Forum Discussion
Arcamper wrote:bpounds wrote:fireman41 wrote:
Not true my 2013 has full manual hubs. Unless you physically turn in the hubs the front axle will not be engaged.
Is it a Superduty? If so, I think you are mistaken. If you look at the hub dial closely you will see it has AUTO and LOCK positions. You can force them locked, but you cannot force them unlocked.
But I've been wrong before.
The Ford Superduty system that had Auto and Lock on the hubs was a vacuum operated system. They were free spinning until you put the shift on the fly selector in 4wd hi or low. Then a small electric valve under the hood, passenger side right next to the vacuum pump applied vacuum to the front hubs. The lock position was a safety in case of failure in the auto system. You could pull the connector off that valve and put the truck in 4 low without locking in the front wheels thus forcing low range without actually being in 4 wheel drive.
It was not the best system out there and I had problems with it twice.
This is my 2013 F250 hubs. Just free and lock, no auto no vacuum
