Hi folks,

2011, F-350 4x4.

Currently it's -30C here. Last night, I pulled into the driveway with 4 wheel drive engaged. Nothing seemed unusual on the drive home. Our town has over 1 foot of snow on the roads, so I was locked in for the 6km drive home on residential/rural streets.

When I woke up in the morning, having not disengaged the 4x4, I backed out of the driveway and got stuck in the street. I looked and the 4x4 light was on, and the switch was in 4H, but the front hubs were clearly not locked. I tried shifting back and forth to no avail and then just did a manual hub lock and went about my day.

Later in the day, I unlocked the manual lock and the auto locks seemed to lock up as per usual.

This morning, I backed out of the driveway in 4x4 and drove forward on the street in the snow and the hubs were clearly locked. When I got to the corner about 300meters away and went to accelerate onto the thoroughfare, the rear wheels just spun with no power to the front, again, no hubby locky.

I asked my dealer and he said it's just cold. I asked another guy and he said that it's a vacuum leak. I asked another guy and he said that they have an electronic actuator that unlocks them when the key is off and they didn't lock up again in reverse and then didn't lock right up in forward and didn't roll far enough to lock.

Ummm, okay. I guess. But why did they unlock on day 2, and do they unlock when I turn off the key?

These are all Ford guys that said this, so I'm a tad confused. This ain't my first rodeo, but it's my first go round with this problem. My last SD had a left front hub that wouldn't unlock, but never had this kind of problem.

Any thoughts?

Thanks!

 

Cold temps are effecting the vacumn diaphams. Leave your hubs lock and just use the switch to engage the fronts till it warms up.

 

Just leave hubs manually locked in and unlock them when it warms up in the spring.

 

Thanks guys, I sorta figured. I'll just leave them locked.

Cheers!

 

-30 that is no joke cold

 

Yeah, it's cold here these days. You know it's cold when you'd rather sit, stuck in the street and eat your lunch, than go out in the cold and manually lock the hubs. It will warm up in the Spring. :/

 

Lots of things don't like to work at -30, including me.

 

htimst- Just noticed this thread. Had an almost identical scenerario w/ my 2011 F-350. But didn't notice it until -42. I live in the hills above the city where it's usually 10-20 degrees warmer (we love the inversion effect). Drove down to the city (-42), parked for almost an hour, pulled into traffic and immediately had 2-wheel drive only Couldn't come up with any other options but to manually lock the hubs and Viola! 4wheel drive again. Have never felt the need to keep the hubs manually locked in any of my vehicles until this happened. Good to find out it's just the temp.