Well just replaced most everything in the front axle. Hubs, vacuum seal, dust seal, inner seals and calipers. I also cleaned the autolock hubs. Fist time I used them they worked. I tried again today and no 4wd. I checked the vacuum lines and they are all intact. Not sure what to do next.

 

Do you have a vacuum pump? Start looking for leaks.

 

Do they work when you manually lock them?

Stewart

 

yes they work manualy. It is acting the same way it did before I cleaned them.

 

When you replaced everything, did you check the lines for leaks, like Andy suggested?

Stewart

 

I inspected them. I did not see any sign of damage. I do not have a way to test them that I know of.

 

Suggest you "T" off one of vacuum lines to hub with a vacuum gauge.

That will tell you if hubs are still leaking or if they are getting vacuum.

Easiest way to tell if hub is leaking is to blow into vacuum line to hub. If you cannot blow thru it's good. If you can is bad.

The gauge will also tell you if vacuum solenoid is working right or not.

 

What engine do you have? Your sig isn't showing.

If you have a 7.3L, turn your keys to the "on" position to power up your vacuum pump to fill the line. That will allow you to track down the leak.

Stewart

 

sorry its a 2005 6L EB with too many upgrades to list

 

Not very up on my 6.0L knowledge, but it's still a diesel and it doesn't make vacuum so you have a pump. Turn the key to "On" and see if you can find the culprit after your pump turns off.

Stewart

 

Working Auto locking hubs on a Superduty / Excursion = Unicorn. Does anyone know if there's an aftermarket alternative Auto Locking Hubs. I don't mind getting out to lock my hubs but the wheel caps have to be removed to do so.

 

I must have a unicorn. Mine work fine.

 

I thought mine worked fine also. That is until I ran a AE code scan.

 

On my last ex there was a valve where the vac lines meet and go to the hubs. On a 7.3 its on the passenger side between the pump and the battery, high on the fender. Mine was bad, replaced it and they worked fine.

Its got two vac hoses and an electrical connector. Can't remember the name of it now, pretty cheap to replace too

 

Took one of Mike's suggestions and replaced vac lines with high quality silicone lines. Fixed my A/C and 4wd. Worth it for the $20 it'll cost ya in tubing.