My dad bought a boat last spring. He has a 09 F150. Last month the rear diff popped. Shop said it had water in it.

Thinking back I do know that there were at least 2 times when the diff was in the water. maybe not completely submerged but at least once was pretty darn close.
They mentioned the seals looked worn. So now I am thinking about did the water get in because of bad seals? I am doubting it because it never dripped any oil out. So the seals were good enough to hold oil in but not hold water out? Doesn't seem right.
So I am thinking in actuality that it maybe got in through the vent. So I am wondering about relocation of the vent. put a tube on it and move it up somewhere higher on the frame.
I know Ford says change the oil every time the diff gets wet. But seriously?

For other boaters I would like to know your thoughts and what you have done with yours.
Thanks

 

Is it a 2wd? My trucks are 4x4's and all have their vents extended up into the frame with a hose. I've only had to go axle-deep a couple times, but never taken in water.

 

No it is 4x4.

I haven't been under the truck since he had the rear rebuilt. It is still winter here. Just trying to make a plan for spring to do some prep work on the truck as well as the boat before we go out the first time. Lakes should be nice and full here this year after all this snow and flooding

 

It should have a vent tube already on it from the factory, with the end of the tube going up along the frame.

Sometimes they get loose and dry rot and crack. The tubes also tend to expand over time and become loose where it goes over the vent nipple.

You can replace the tube, attach the vent end up near the top of the frame, and also put a small hose clamp around the tube at the vent nipple to make sure it doesn't come off easily.

 

I was under my truck last week adding some stuff and I saw the vent hose looped up over a cross member. I got a fuel line filter I had for the garden tractor and inserted it promptly. Just those disc type as I change them out yearly. It will keep dirt, moisture and critters that like those places out.

 

Good to know. I honestly didn't expect it to be extended from the factory. I would expect that if they rebuilt the diff that they would check that vent upon reassembly but I haven't seen the paperwork from the shop yet.

I think I will be definitely checking it before we take the boat out.

Thanks guys.