I own a 2003 Superduty. I was putting my boat in a lake with a real shallow launch so I had to back in until my back tires were completly under water. Afterwards I wanted to make sure the vent tube on my rear axle was long enough but I couldnt find it. Is there not a vent on my rear axle?
I just looked at my 03 F-250, and I have one. It's on the left (driver's) side. Look at the tee where the rear brake hose meets the 2 steel brake lines. It's incorporated into that tee. On mine, the vent hose goes up from that tee to under the bed.
I found it. It was covered with grim and dirt so I didnt see it before. Unfortunatly the is no hose. So should I be worried? It wasnt underwater for more than a few minutes. I drove it 200 miles home afterwards. No noises or anything.
Time for a rear fluid change. Not even considering that the vent was underwater this time, how long has it been going without a vent tube, which could allow dirt, water spray from a wet road, whatever into the differential.
And you'll want to get a vent tube on there. If you look around, the original tube might be hanging around loose under there. It would have gone up to a open V shaped fitting connected up under the bed somewhere.
A hot diff soaked in cold water will pull a vacuum and potentially suck water in the disconnected diff. vent. You need to check/change it immediately, and possibly change it twice. Getting the diff good and hot with the new lube should drive off any remaining water, so I'd recommend a road trip after you change the oil.
Ok I'll change it. I cant find the disconnected hose anywhere so I gonna have to buy a new one. Who knows how long its been gone. Ive only owned the truck 5 monthes. Any idea what oil I need to put back in it??
While you have the cover off, I would lift each side of the axle with a hydraulic jack under each shock mount 1 at a time for a few minutes. This is just in case water got into the axle tubes. If the rear end was under water for a few minutes, you might have quite a bit of water in there.
Know for sure the rear has a vent and almost sure the front does to but not 100% sure - vent is to allow gasses to escape as the oil in the pumpkin heats up - if they weren't vented the pinion seal would get blown out. (Ask me how I know - plugged vent on a 99 F150 + 150 miles @ 65mph = blown pinion seal and a diff soaked in gear oil)