Auto-Lock hubs

[flogvul]

I have a 2000 f250 superduty 4x4. The hubs on the front tires say Auto-Lock. What is the difference between the two and the purpose? Just curious and thanks.

[mountainlander]

In 'auto', the hubs will lock by vacuum power when you engage the transfer case, and unlock when it's disengaged. 'Lock' manually locks the hubs regardless of what the transfercase is doing.

[Raul@Stealth Automotive]

auto is just that its the position you put it in to keep the hubs free but when you turn the knob up front they are air actuated and they auto lock them without you having to go out and physically lock them.... the lock position is just that it locks them in

[flogvul]

So what is the purpose of having them in the lock position? Sounds to me Auto is the position to have them in.

[mountainlander]

Originally Posted by flogvul

So what is the purpose of having them in the lock position? Sounds to me Auto is the position to have them in.

Yes and no. If you are in a highway situation where you are running through patches of ice or snow, it would be good to use auto when popping in and out of 4x4. If the vacuum system fails, or if you are in deep mud or snow where you will be constantly in 4x4 one might choose to manually lock the hubs in to avoid wear and tear on the vacuum system...

[flogvul]

Thank you. Anybody have any thoughts on pulling or towing in Auto or Lock? One preferred or better to use than the other?

[magnumpeei]

Originally Posted by flogvul

Thank you. Anybody have any thoughts on pulling or towing in Auto or Lock? One preferred or better to use than the other?

If you know you're going to need 4x4 for sure, put them in Lock. For everything else, go with Auto.

[mountainlander]

This brings up another question. Maybe one of the techs will speak up.

What order does stuff happen when you shift into 4x4 with auto lock hubs? Do the hubs lock first, then the t-case engage? Or does the t-case engage then the hubs? Or simultaneously? Even more important, can you shift into 4x4 'on-the-fly' when the hubs are in manual lock position?

[99bigred]

i believe it either it has to be in neutral or the clutch has to be in but not 100% sure

[4everlearning]

Originally Posted by mountainlander

This brings up another question. Maybe one of the techs will speak up.

What order does stuff happen when you shift into 4x4 with auto lock hubs? Do the hubs lock first, then the t-case engage? Or does the t-case engage then the hubs? Or simultaneously? Even more important, can you shift into 4x4 'on-the-fly' when the hubs are in manual lock position?

This depends on what you have. if you have the electric knob on the dash then no you cannot shift on the fly. The main trans has to be in neutral or the clutch pushed in. but if your lever is on the floor you can shift of the fly to High range with the hubs in lock but not in auto.

Also the transfere case is what engages first then when your rear tires slip the hubs (in auto) lock, and can cause shock to the front end.