Rear differential submerged

So the lakes are really low this year due to the drought conditions. Last two times I launched, I had to back in so far that the truck was almost launched as well and still wrestle the boat off the trailer.

Of course, I was a bit concerned about if the rear diff vent got submerged so I got under the truck later to inspect. Great! I see a factory relocation of the vent via rubber hose coming off the diff. Drop the spare tire to find the termination and WTH, who came up with this arrangement? The vent is clipped into a fancy holder a full two inches (maybe) above the rear diff where the vent would be in it. What good is that? There’s plenty of length and suitable locations to locate the vent much higher up. They went to all this trouble and that’s where they put it?

The good news is that there was no water intrusion. I suspect that airlock, small diameter tubing and relatively short duration submerged all contributed to the lack of water ingress.

My other gripe is the rear takes something like 2.2 qts. You can’t design it to take an even amount so I only have to buy 2 qts?? Not have .8 qts left in another container for years on end until the next change…

I relocated the vent myself…just a reminder to others, don’t forget to service the rear diff if you do a lot of backing in to launch…

Could be worse. Your vent for the charcoal canister could be located back there like it is on a Subaru. Got a little water in mine, $700 parts, 6 hours labor. Good that it was under warranty. BTW, I didn’t even submerge mine, the water splashed up on it.

I didn’t even realize rear differentials were vented. The few I’ve seen looked like they were completely sealed.

I’ve often thought all I needed to drive through high water is a snorkel for the air intake (ignoring, for the moment, issues of mold in the upholstery).

That must be a scary moment when you think your truck might sink into the lake.

Yes, that would classify as worse!
Six hours of labor??! Sheesh. Seems a bit extreme for that kind of work. Must be embedded like a tick under there…

The differential has to be removed. But it was a two stage failure, first I got a code for the filter ($200), one hour diagnostics, two weeks waiting for the part, 2 hours to drop the differential to install.

Then a week later got a code for the canister air pump failure. One hour diagnostics, two weeks for new canister assembly ($500), two hours to install.

I haven’t seen an unvented diff. Many just have a small plastic part with a loosely fitting cap stuck in the housing. Diffs get pretty hot actually and that causes the air to expand. If it wasn’t vented, that would force the lubricant out of the seals.

I was up to the rear door seals and the tailgate seal was being lapped upon by the waves. It’s at this point you say, 4 wheel drive, don’t fail me now!

I wish I could convert to a roller trailer but the boat isn’t designed for it. I’m going to install bunk slicks made from PVC lumber to make it slide off easier in case this situation continues into next year.

Year? Make? Model?

Learn something new every day, luckily my lake I just have to get the rear wheels to the water for the perfect depth. Something to be aware of in future launches. I had a tilt trailer on the previous boat, pull a pin and the hitch leg unlocks from the trailer allowing the trailer to tilt independent of the leg the hitch is on, I do not know if that would help launching or yanking a boat.

When I used to off-road a lot in the Colorado mountains, forging creeks and rivers is a common thing. The water would sometimes get high enough it would come through the doors. So the differentials on my truck were getting dunked all the time. For some reason the diff on Ford trucks sits very low to the ground. Anyway, the owner’s manual said anytime it got under water the owner had to drain and refill both front and rear differentials, so I did that job a lot of times. I would sometimes do that and re-lube the front wheel bearings every evening at the campsite, for 4 or 5 days in a row until we finally hit dry pavement again.

I’m somewhat sure that all rear ends are vented. Otherwise they would blow seals.

I wonder how ATV manufacturers deal with this issue, especially the ATVs ridden through rivers and mud holes. If you look at pictures of people mud boggin’, you can see them riding their ATVs in rivers where their ATVs are almost completely submerged.

Looking at the manual transmission on my Civic, which also functions as the front end differential, I don’t find any vents, just a fill hole and a drain hole.

All vents and intake on my ATV are routed up to the highest point on the frame under the cowling. I can literally stand on the seat and ride through water as long as the part just below the steering handlebars does not go under. Done it many times. In fact, the very first outing I had to be winched out of a water filled ditch that was too steep on exit to make it on my own. It’s a bit unnerving to submerge a $4500 machine within hours of buying it but that’s what it’s for…

I had an old M38A1 Jeep that was built to ford water up to the level of the windshield. There was plumbing from every component to vent into the breather that was mounted at the windshield. The bellhousing was sealed and vented to keep the clutch dry and the secondary ignition was sealed and vented as well. I have driven those Jeeps into the surf until water was up to my waist

Keep looking. It should be at the very top of the change lever assembly housing that bolts to the top of the transaxle.

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hmmm … Driver above seems to have a misconception about which end of the rig goes into the water first!

And I thought I had seen it all re boat ramp misshaps.

I wonder if salvage rights cover getting that mess on dry ground again?

That doesn’t bode well for the fishing in that area. A vehicle submerged in water is an environmental disaster for fishermen. I hope nobody was hurt.

A co-worker once bought an Isuzu Impulse (?), a Japanese Chevette with a turbo. During the mandatory undercoating the applier taped up the differential vent. He never untaped it. During the first multi-hour drive, differential grease blew out of both sides of the rear axle.

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It’s not quite as bad as it used to be. At least the gas is in a sealed system. Short term, not much is going to make it’s way out. Not ideal but if they get the tow rig there in an hour or so, it’s probably a minimal impact- to the lake that is…I’ve seen some smaller stuff sunk like snowmobiles and ATVs in the winter/spring. Much farther from shore and harder to salvage. Amazingly, even after a couple days, no noticeable slick and gas still in the tank. Fines rack up fast!