4WD vs AC? - Ford Powerstroke Diesel Forum
Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 08-07-2006, 01:38 PM
Powerstroke.org Rookie
 

Join Date: Aug 2006
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Question 4WD vs AC?

Ok, just bought a 2000 F350 7.3PSD. When I switch to 4WHigh with the AC on, the damper switches from the dash air vents to the windshield air vents. After about 30 seconds to a minute, it switches back to normal. I think that the 4WD is activated by vacuum but I don't think the AC damper is. If the AC damper is, could the 4WD vacuum be borrowing from the AC damper vacuum?
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 08-07-2006, 01:45 PM
Power Strokeaholic
 

Join Date: Nov 2005
Location: Clarksville,Ohio
Posts: 1,354
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
you have a vacum leak some where. the place i would start is the lines that go from the frame to the hub's on the back side. thats the cheapest thing to replace and a pretty common pont of leaks. there's also the yellow o-rings in the axle that seals the hub to the axle i think. marc and some one else can be more specific for you. i just replaced mine with super winch manual hub's. no problem's
Reply With Quote Quick reply to this message
  #3  
Old 08-07-2006, 01:57 PM
Powerstroke.org Rookie
 

Join Date: Aug 2006
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
So, you don't think it is even going into 4WD? What about the vacuum canister? Could there be a leak there?
Reply With Quote Quick reply to this message
  #4  
Old 08-07-2006, 05:15 PM
Banned
 

Join Date: Jan 2006
Location: central coast, california
Posts: 0
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
The AC and 4WD both use vacume provided by the little electric vacume pump. The most common place for a vacume leak causing one or both to be inop only in 4x4 is the backside hub seals, or excluder seal. It is a press fit seal and they deteriorate over time...
Reply With Quote Quick reply to this message
  #5  
Old 08-09-2006, 12:34 PM
Powerstroke.org Rookie
 

Join Date: Aug 2006
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Some say just manually lock'em in and forget that you ever had a problem. It may hurt your mileage but you won't have to worry whether there is enough vacuum pressure or not to lock them in automatically.
Reply With Quote Quick reply to this message
  #6  
Old 08-09-2006, 12:45 PM
Power Strokeaholic
 

Join Date: Nov 2005
Location: Clarksville,Ohio
Posts: 1,354
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
thats true. but why put undue wear and tear on the front drive line?? just order a set of after market manual hubs. it'll save you money in the long run.
Reply With Quote Quick reply to this message
  #7  
Old 08-09-2006, 12:56 PM
Powerstroke.org Rookie
 

Join Date: Aug 2006
Posts: 11
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Maybe I am not understanding something about how the system works.
I have hubs that I can lock in manually or allow the automatic system to lock the hubs and diff. at the same time. I thought. Maybe the diff is always locked in and the switch to 4Hi just locks the already-turning axle to the hub, I am not sure. If I already have the option to manually lock my hubs, why would i need aftermarket lockers?
Reply With Quote Quick reply to this message
  #8  
Old 08-09-2006, 01:05 PM
Power Strokeaholic
 

Join Date: Nov 2005
Location: Clarksville,Ohio
Posts: 1,354
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
maybe im not understanding you. are you talking about locking the hubs and leaving them locked or just lock them when you need them? if you leave them locked all the time it will hurt mileage and wear things out in the front end over time. if want to replace them dont spent a couple hunred dollars a piece for factory locks. you can get a pair of warn, super winch, or mile marker locks for about half the cost of one factory lock. but you wont have th shift on the fly feature with those after market locks.
Reply With Quote Quick reply to this message
  #9  
Old 08-09-2006, 05:38 PM
Banned
 

Join Date: Jan 2006
Location: central coast, california
Posts: 0
Thanks: 0
Thanked 1 Time in 1 Post
Feedback Score: 0 reviews
Bottom line is that i personally dont trust the auto function on those hubs, and more importantly, there is a lot of stuff to catch up to speed if you engage the 4 by at any decent speed in auto mode. With them locked in, you dont have that and you KNOW that it is locking in....

Run them locked when you need 4x4, unlocke (auto) when you dont......
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum 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:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

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



All times are GMT -8. The time now is 12:14 PM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

vB.Sponsors