I am new to 4x4 trucks, I just bought my first one which is a 1990 f250 with the 460. it has manual locking hubs. my question is should I have to lock out the hubs for the 4x4 to work? or should it work just by shifting it into 4x4 in the cab? what does locking out the hubs do?
Thanks

 

the hubs are the connection for the front wheels to the axle shaft. so you have to lock in the hubs and shift the transfer case into 4high or 4low. welcome to 4 wheel drive!

 

Thanks for the help

 

The lock out hubs are installed by many because of several reasons. If 4x4 is not needed you can lock out the hubs and it will allow a little better fuel economy and will reduce wear on some of the 4x4 parts because they will not be turning. If you are moving, down a road or elsewhere, and suddenly want four wheel drive all you need to do is engage the four wheel drive and you don't have to stop the vehicle. However be sure that you don't try to engage the 4 wheel drive while you are moving if the front hubs are locked out. Lock out hubs helped me in a bad situation, I broke a front universal joint once while plowing a driveway and was able to drive home safely when I locked out the front hubs.

 

I'm not really saying anything different from what kdwellsr said, adding a little and maybe clarifying a little.

If you are on any surface where you get good traction (like pavement that isn't covered with snow) you should have the transfer case in 2WD.

Any time you know you are going to only be in 2WD it's best to put the hubs in the "free" (or "unlocked") position.

You can drive with the hubs locked in 2WD, all it does it use a little more fuel, cause a little more wear on your front drive line and maybe cause a little vibration. It's often desireable to do this if you think you might need 4WD soon (like driving after a snow storm where roads are sometimes clear and sometimes snow covered). Or when you've been in 4WD and don't need it anymore but don't want to get out to unlock the hubs right then.

If your hubs are already locked you can shift into 4WD while you are moving. It's best to back off on the gas a little and not be turning. But as long as you aren't spinning your tires while you do it you're probably OK. you do need to stop before shifting in or out of low range in the transfer case.

Do not shift into 4WD while moving if your hubs are unlocked. It will make nasty noises. And being in 4WD with the hubs unlocked is pretty pointless anyway, you don't have 4WD unless the transfer case is in 4WD and the hubs are locked.

 

Curious why you say not to use 4wd without hubs locked? I've used low range several times over the years without locking hubs. Usually when backing trailers in tight spots, seems to make it easier with a stick. Never noticed any noises or problems. Obviously if it's slick you'd want to lock hubs in.

Just noticed the "while moving", nevermind.

 

I also have used 4 low range without having the hubs locked...It will indeed engage transfer case into low range and will allow you to move slowly in forward or reverse direction but... you will not have four wheel drive working. The transfer case will be engaged and differential will be engaged but the front tires will not be engaged unless the hubs are locked in. The process of unlocking the front hubs puts the front tires in a free wheeling condition.

 

There's also the golden rule of 4-wheelin' to pass on...

You must ALWAYS wait until you are driving through some viscous substance at least 1" taller than the top of your boots before you remember that the hubs aren't locked.

 

Yes, 4-low with the hubs unlocked is useful. I just wasn't trying to get that deep. And as you noted, my main point was not to shift into 4WD while moving with the hubs unlocked

 

Made me LOL about the 1" taller issue. Brings back a bunch of muddy issues. Lots of good memories... Didn't call them good memories at that time tho.