Why would both ESOF hubs stop engaging at the same time? - Diesel Forum - TheDieselStop.com
1999-2007 General Questions General questions related to 1999-2007 Super Duty trucks. If it doesn't fit the other categories, post it here. Gas engine discussion that pertains to all models is allowed. Specific gas engine questions should use the Gas Engines forum.

 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 12-27-2013, 06:09 PM Thread Starter
Junior Member
 
jdrake's Avatar
 
Join Date: Dec 2013
Location: Ohio
Posts: 18
My Photos: (0)
Feedback Score: 0 reviews
Why would both ESOF hubs stop engaging at the same time?

Up until recently my ESOF hubs have been working fine (2000 F250 7.3 218K miles), though I don't often have occasion to use the 4wd in Ohio. Now recently they won't engage automatically. Manual engagement is fine. It would seem to me that if it was a vacuum line to the hub only one side would fail (the one with the bad line)? So maybe its the solenoid that failed? But the heater controls work fine. What should I be looking for and how do I diagnose.
Before I get too many comments, I know that most people like to put manual hubs on and toss the OEM hubs. If I were a serious off-raoder that would make sense. But I'm not. I like the convenience of having 4wd on demand without having to turn all the axles/bearings/gears 99.5% of my driving hours. Should save fuel as well as wear and tear. Bottom line, I want to keep the ESOF hubs even if I have to rebuild or replace them. Heck, they've gone 218K on the first set. If I get 200K out of another set that should do me.
jdrake is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 12-27-2013, 07:42 PM
Senior Member
 
Join Date: Mar 2000
Location: Hallsville, MO USA
Posts: 236
My Photos: (0)
Feedback Score: 0 reviews
The vacuum-operated thing probably failed, or your luck just ran out on the hubs in general. I think I put two of the vacuum switch things on my '99 in only about 135,000 miles. Best advice, forget the hubs are automatic and use them like manual hubs. If your heater goes nuts, pull the line to the switch thing and put a pen cap in it to block it.

-- 2013 F-350 psd, 4x4, cc, lb, Lariat
hillco is offline  
post #3 of 6 (permalink) Old 12-29-2013, 08:50 PM Thread Starter
Junior Member
 
jdrake's Avatar
 
Join Date: Dec 2013
Location: Ohio
Posts: 18
My Photos: (0)
Feedback Score: 0 reviews
Why would both ESOF hubs stop engaging at the same time?

I apologize if this is a repeat. I thought I posted it 2 days ago but don't see it anywhere (I'm new here).

My ESOF has been working fine until recently but went to use it this week and the hubs don't lock. I can manually lock them, and did, and was able to use the 4wd many times this week as my road is flooded. Seems like if it was a vacuum line leak it would only affect one side? Might it be the solenoid? How do I check? Please use few acronyms as possible as this is my first diesel (2000 F250 7.3 200K). Also, I like the auto hubs and am not a serious off-roader so want to keep them. Better fuel mileage and less wear/tear on drive train. Thanks
jdrake is offline  
Sponsored Links
Advertisement
 
post #4 of 6 (permalink) Old 12-29-2013, 10:44 PM
Senior Member
 
Join Date: Nov 2004
Posts: 652
My Photos: (0)
Feedback Score: 0 reviews
Think of the hublocks as click type ball point pens. Push them on with a vacuum pulse, push them off with another. The solenoid provides 15 inches of vacuum to apply and 7 inches to unapply. Any leak will stop operation of both hublocks as they are tied together. Lines, vacuum hub seal failure due to bad ball joints, wheel bearing failure, solenoid failure, hublock failure of their vacuum diaphragm, torn hublock or wheel bearing o rings, vacuum pump failure.... the list goes on. Buy a handheld vacuum pump with guage. disconnect the lines at the solenoid. Check for adequate source vacuum once the pump turns off- over 15 inches Hg. If that is fine, put the source vacuum back on the solenoid and the pump gage on the outlet of the solenoid. Check for 15 inches to apply and release in 4x4 and 7 to apply and release in 2wd. The 4x4 module can hold one on or off till a timer has elapsed, IIRC 2 minutes. If you got good readings there, you have a leak somewhere in the hublocks/bearings/lines. Remove each line at the spindle. block with a golf tee or something of the like. apply hand pump vacuum to check the integrity of the lines. Check each hub with the hand pump. Should hold 15 inches Hg with no leaks. Do this with the wheels off the ground and spin them hublocks engaged and disengaged. You will find your fault eventually.

Dad always said,"Knowledge is limited but stupidity knows no bounds."
YT90SC is offline  
post #5 of 6 (permalink) Old 12-29-2013, 11:25 PM
Lifetime Supporting Member
 
klhansen's Avatar
 
Join Date: Jan 2003
Location: Eagle River, Alaska
Posts: 24,751
My Photos: (180)
Feedback Score: 0 reviews
Quote:
Originally Posted by jdrake View Post
I apologize if this is a repeat. I thought I posted it 2 days ago but don't see it anywhere (I'm new here).
Merged your two posts, as they both had replies.

Welcome to TheDieselStop. Looks like the guys are giving you some good advice.

klhansen
Moderator
klhansen is offline  
post #6 of 6 (permalink) Old 12-30-2013, 10:26 PM Thread Starter
Junior Member
 
jdrake's Avatar
 
Join Date: Dec 2013
Location: Ohio
Posts: 18
My Photos: (0)
Feedback Score: 0 reviews
This is great! thank you all for the troubleshooting instructions (and in layman's terms too) and for merging my double post. Now, to get to work!
jdrake is offline  
Sponsored Links
Advertisement
 
Reply

  Diesel Forum - TheDieselStop.com > 1999-2007 Ford Super Duties > 1999-2007 General Questions

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Diesel Forum - TheDieselStop.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome