# 05 f250 4x4 not working



## fatheadon1 (Dec 27, 2007)

Shift on the fly when i hit the switch to 4x4 i get nothing no light and no 4x4 if i turn the truck off and restart it it goes in fine anyone have a clue what could be wrong again truck is an 05 f250 diesel 4x4 85000 miles


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## hydro_37 (Sep 10, 2006)

Maybe it is a loss of vacuum? Just a guess.


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## Gicon (Oct 1, 2005)

Yea, I would think there is a problem in the hubs.


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## wrtenterprises (Mar 10, 2001)

We had a couple of small events this week, and I found that my Super Duty had the same issue. Needless to say, waiting until the first event of the season to find a problem this large is a real anxiety builder! However, we completed snow removal the ole fashion way, with the Snow Commanders, and still made plenty of cash.

I have ordered a set of Warn manuals, and they will be installed on Black Friday. $220.00 per set ( nephew is a parts manager. ) No more vacuum shift on the fly for me......

Wayne


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## ZamboniHDB (May 8, 2004)

No 4 x 4 light on the dash wouldn't be as a result of a vacuum leak in the lines or hubs. The transfer case isn't operated off of vacuum either. Obviously an electronic malfunction like a sensor, switch, relay, or module. A trans shop should be able to diagnose it and not throw random parts at the problem to solve the issue.

Just my .02¢


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## Bernie Lomax (Mar 15, 2007)

There are several relays in that system. Also could be the shift motor. Those ESOF systems are a nightmare. Never again on my trucks.


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## RobbieB (Feb 9, 2008)

I would hazard to guess your transfer case motor is going out. The 4x4 light in the dash is powered off of the output wire from the motor so if it dies the light won't come on. Had it happen to my Excursion.


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## Deere444H (Sep 5, 2006)

If the light never lights up, It never Shifted the transfer case, Try slowing down, and trying that, if your trying to go into 4 lo. you need to be stoped and in Nuteral. you may just be puting it in wrong, refer to the manual, and double check you method, the system is pretty simple, Two relays, controlled by the SJB, and the shift motor, the shift motor has a sensor that changes the light, and commands the PCM to lock the front hubs.. Havent seen many problems with the 05 up front ends, TONS with the 99 to 04 front ends, but sounds like an electrical/transfew case engagement, not Front Vac. Hub issue. Ill look at the workshop manual tonight and see what it says about engagment speeds


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## Deere444H (Sep 5, 2006)

Alright so heres some info about shifting it... hope it helps. The operator can switch between 2H and 4H mode at speeds up to 55 mph To engage or disengage 4L, vehicle speed be less than 3 mph the brake pedal pressed and the transmission in NEUTRAL or clutch depressed.


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## Ramairfreak98ss (Aug 17, 2005)

well my 06, just past the standard warranty 36,250, i tried 4x4 in some light mud with my trailer, 4x4 light lights up but no thunk/4x4... took it to the dealer they said its fine picked up, still fine so not sure what it was. Mine has the shift on fly too.


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## Deere444H (Sep 5, 2006)

if the light is on, the transfer case has shifted, and the light is on from the position sensor, so it in fact has shifted, or.. the motor has at leaste moved where the sensor is, if the four wheel still dosent work.. suspect your auto lock hubs, to verify.. shift into four wheel,, then move the hubs from the AUTO positon To the LOCK positon. give it a whirl....


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