Need help getting 4wd working
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Trailering
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Need help getting 4wd working
I have a 2015 ford f250 with 6.2 gas burner. I have seen a few post with diesel engines and they have a vacuum pump. I thinking my gas burner creates vacuum so no pump for me. My light on dash comes on and I can hear it switching to 4wd and out with turning of selector ****.
So I’m needing somebody to walk me thru trying to diagnose the problem. Should I pull the lines down by the front tires and check for vacuum on both sides of where I split line. I understand to do this on both sides? Or should I try something different first. Thanks for the help.
So I’m needing somebody to walk me thru trying to diagnose the problem. Should I pull the lines down by the front tires and check for vacuum on both sides of where I split line. I understand to do this on both sides? Or should I try something different first. Thanks for the help.
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From: Billings, Montana
I just had the same issue with my 2012, luckily it was an easy fix for me. Here's a thread I wrote about it, hopefully yours will be as easy. https://www.ford-trucks.com/forums/1...ubs-fixed.html
So basically what I'd do first, is check to make sure the solenoid vacuum switch is working, on mine its located on top of the passenger side fan shroud (see the pics in my thread) you want to pull the top tube off the switch then hook a vacuum gauge to the switch, it should show 0 when you connect it. The start the truck, turn the control to 4x4 and check the gauge again. If its working you should now show a vacuum. If it looks good then hook everything back up and pull one of the vacuum lines off on of the hubs and hook the gauge off the one you pulled and try it again. If you're showing vacuum that means the seals on the other hub are good, if you don't show any vacuum try clamping the vacuum line on the other hub and see if you show vacuum, if you do then your seals on that hub are probably bad. If you still show no vacuum, then your could have a break in the vacuum line else where. Repeat the tests from the other side to test the other hub seals. Let us know what you find out.
So basically what I'd do first, is check to make sure the solenoid vacuum switch is working, on mine its located on top of the passenger side fan shroud (see the pics in my thread) you want to pull the top tube off the switch then hook a vacuum gauge to the switch, it should show 0 when you connect it. The start the truck, turn the control to 4x4 and check the gauge again. If its working you should now show a vacuum. If it looks good then hook everything back up and pull one of the vacuum lines off on of the hubs and hook the gauge off the one you pulled and try it again. If you're showing vacuum that means the seals on the other hub are good, if you don't show any vacuum try clamping the vacuum line on the other hub and see if you show vacuum, if you do then your seals on that hub are probably bad. If you still show no vacuum, then your could have a break in the vacuum line else where. Repeat the tests from the other side to test the other hub seals. Let us know what you find out.
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Trailering
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Thanks for the response and the link to the thread. I had no idea where solenoid was located. I also tried to turn hubs to lock but it didn’t help. This was left out of my original post because wife was waiting for me to eat with her and I rushed it. So with this new information about hubs not locking manual or with switch on dash.
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From: Billings, Montana
Thanks for the response and the link to the thread. I had no idea where solenoid was located. I also tried to turn hubs to lock but it didn’t help. This was left out of my original post because wife was waiting for me to eat with her and I rushed it. So with this new information about hubs not locking manual or with switch on dash.
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Trailering
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From: Billings, Montana
See if this helps https://www.ford-trucks.com/forums/8...se-issues.html or this https://www.ford-trucks.com/forums/1...4hi-fixed.html
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Thanks for the response and the link to the thread. I had no idea where solenoid was located. I also tried to turn hubs to lock but it didn’t help. This was left out of my original post because wife was waiting for me to eat with her and I rushed it. So with this new information about hubs not locking manual or with switch on dash.
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Trailering
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Thanks for the help and this definitely gives me a starting point. I will report back what I find out. It may take a couple days because we are expecting heavy rain when I get off work so maybe tomorrow night before I can check the 4wd driveshaft.
Also can someone tell me where my shift relays are on a 2015 6.2 gas? Thanks
Also can someone tell me where my shift relays are on a 2015 6.2 gas? Thanks
Last edited by Rickyb1968; Nov 29, 2022 at 05:32 AM.
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Joined: Dec 2005
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From: Billings, Montana
Thanks for the help and this definitely gives me a starting point. I will report back what I find out. It may take a couple days because we are expecting heavy rain when I get off work so maybe tomorrow night before I can check the 4wd driveshaft.
Also can someone tell me where my shift relays are on a 2015 6.2 gas? Thanks
Also can someone tell me where my shift relays are on a 2015 6.2 gas? Thanks
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Trailering
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I was able to test the front driveshaft this evening. It does lock up when the selector is in 4wd. In 2wd it free spins. So I’m guessing my next step is to check vacuum. I still don’t know why 4wd didn’t work when front hubs in lock.
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From: Billings, Montana
Well when you manually lock the hubs in it should work, the vacuum hubs would have no affect when they're locked in manually.
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From: Southern OH
Did you lock both hubs with it in 2wd and see if the front driveshaft turns?
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Trailering
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No I didn’t do that. I will try that tomorrow evening. What are we trying to figure out here? I’m just trying to learn as we go.