ESOF Won't Engage........

[Tbar]

Vacuum pump runs, pulls vacuum and shuts off but neither hub engages. They do lock if I work them manually. The drive shaft to the 3rd member is engaged as well.

Just got the truck back from the shop after the wreck......they forgot the yellow orng seal when they replaced the unit bearing assy so I made them take it apart and install it. Outer seal is new and in place as well.

Still no luck. Any suggestions.....and no I don't want to get rid of ESOF.


Tbar

 

[NevrKnow]

My hoses were dry rotted on each side of the axle. That's a start. Yellow o-ring replaced? CHECK.

Must be another place for a leak. Trace the lines from the pump all the way down to the diff. ?

When you think about it, there's not many places to go. Pump OK ? CHECK.
Lines to the diff hold a vacuum? CHECK. That only leaves the hubs themselves.

Someone smarter then me may have a better idea. Good luck man.

 

[JLDickmon]

got a vacuum gauge?
I'd check the vacuum to the knuckles...
backtrack from there if/as needed....

 

[atk]

raise front tires off the ground, take a vaccum pump and apply vaccum to each side. this will tell you if the problem is in the knuckles/hubs....

 

[JRNOLL]

I'm not sure what all is controled by vacuum on our trucks. Sometimes heater valves ,vent and a/c flapers may be. These are also prime suspects for leaks.

Hope this helps. Joe

 

[dpantazis]

what about the INNER seals? if they fubar'd the outer, then i'd put money on the inners too. or is that what you mean by the yellow ones?

just for giggles, i would 'borrow' a known good locking hub and put it on your truck to make sure the diaphragms on the hubs are not shot.

there are some silly plastic barbed 90's that terminate the hoses to the hubs, i might check those too.

dp

 

[rammertide07]

After I had my transmission rebuilt, my ESOF wouldnt work either. I took it back up the shop, the raised me and the truck up....I saw him go under the truck with a pry bar.....took my back down and tried it again succesfully. When they put the plug back on they did not snap it back good at the transfer case. I remember trying to push in on it before I took it up there and it felt secure to me....guess thats what the pry bar was for.

 

[JLDickmon]

Vacuum pump runs, pulls vacuum and shuts off but neither hub engages. They do lock if I work them manually. The drive shaft to the 3rd member is engaged as well.

Just got the truck back from the shop after the wreck......they forgot the yellow orng seal when they replaced the unit bearing assy so I made them take it apart and install it. Outer seal is new and in place as well.

Still no luck. Any suggestions.....and no I don't want to get rid of ESOF.


Tbar

Lance.. you get this fixed??

 

[Tbar]

Lance.. you get this fixed??

No.....not yet. Its been too hot to mess with it. I need to see if I have a vacuum gauge to test the hubs and lines.


Tbar