Thinking of a 4x4 diesel with the locking hubs on the wheels. Wasn't sure how they worked. If unlocked does the truck remain in 2 wheel drive even if put into 4 wheel drive? The salesman didn't seem to make sense. I had a jeep with locking hubs and I assumed they worked similar. It would be convienent to back a fifth wheel into tight spaces with the lower gearing with out the front wheels locked due to binding up the system. I would appreciate some education on the locking hubs. Thanks.

 

You can engage and disengage the 4 wheel drive without touching the hubs. I was curious about them myself, but read here, that the manual locking hubs are a back-up, in case the vaccum switches fail to operate.

 

What year vehicle is this on? There are big differences between the 97 and older and the 99+ vehicles. The older 97s had true locking hubs. These were available in automatic and manual versions. Both versions were 100% mechanical in design. The 99+ trucks were a different design and used 2 different versions. There was somewhat of a true manual yet with both lock and unlocked positions, then there was the automatic hubs. These hubs have an automatic position as well as a locked position. These auto hubs are actuated by vacuum which can be prone to failure so a mechanical lock position was added. The true manual hubs both both models will allow you to use a 2wd lo. The older automatics would lock via a cam and spring combination when power was put to the front axle shafts. The newer autos are actuated by a vacuum pump under the hood on the passenger side fender. Both auto hub designs can be converted to a true manual design so 2wd lo can be achieved. Myself I prefer the mechanical manual hubs for a few reasons. Yes I have to get out of the truck to lock them in, but in cases when I know I'm going to need 4x4 I will lock them in inadvance. There are fewer things to go wrong on this design so no vacuum pumps to go out or hoses to break. The conversion for the 99+ trucks is about $160 and can be gotten from Napa (or any other Warn dealer).