This will be my first copy and paste attempt for a post written off-line since the new format. Interesting to see how it transfers.
I used to have to do a lot of editing before to make the sentences line up right.
We had flooding at my hunt camp this year due to all the rains in Georgia. Normally we will pull out if its going real high, but this year it was predicted to not get too high and not last long.
So, we left our campers and several trucks in there along with some folks who wanted to tough it out. The water quickly went over the access road to a depth of several feet like it always does, and the power went off.
The folks in there had a genset, and plenty of food and water.
Plus a boat and cell phones.
I made a couple of supply runs for them. Meeting the boat at the water's edge.
Then the rains came. Finally the water got so high at the camp, they moved all the campers, trucks and equipment to the highest point and came out.
When the water went down, we drove in and looked for damage.
We had picked that place because it almost never floods, plus we had built it up some with loads of dirt many years ago. As a result, none of the equipment was damaged. The water never even got to the bottom of the hubcaps on any of the trailers or trucks.
We moved the trailers back and continued on.
The water level on the main road varied up and down. Some of us drove through it fairly deep. I advised everyone to check the oil in their diffs for water contamination.
One of my friends, took his 4 wheeler home on a small trailer when the season was winding down. After he got home, about 200 miles away, he found oil on his trailer and back truck tailgate. It appeared to be coming from the front main seal on his rear diff.
He drove through water up to the doors in his 2010 Chevy 4wd.
He wrote to ask me what he should do.
I won't post all the back and forth stuff, but basically I advised him to check for water, check for looseness in the input shaft, and make sure the vent tube was not hanging down or kinked.
He said that the vent tube was fine, and was hooked to the vent for his gas tank. The oil in the rear end was low and suspicious looking.
I told him to change it and put in a synthetic. He did, and said that it looked "grayish". After doing that, he has driven it a few times and has heard no bad sounds, nor seen any leaks.
He is still a little concerned, and wrote me the following E-Mail this morning. Below it is my reply. I welcome any comments or recommendations as to what I did or did not say.
Bearing in mind, he is something of a novice at this. He has some mechanical ability, but not a lot of off-road experience.
Here is his question:
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J, since the vent tube goes all the way up to the gas filler cap, I can't figure how water may have gotten in there. How the water got in is still bugging me. Is there something else I should look for ?
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And here is my answer:
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Not really. Water rarely gets into a rear end through the vent tube anymore. Some of the older trucks did not have vent tubes, just a small vent cap.
My Jeep had that.
When they first started putting tubes on trucks, they often did not put them high enough. But after enough people added extensions and moved the tubes higher, the companies learned.
My main worry on your vent tube was a blockage that would cause pressure to build up and force the oil out around the seal.
I'm sure the water got in the same way it always does. Through the front seal and the wheel seals.
They are designed to resist pressure and leaks from inside, not outside. Plus they are designed to last a long time.
To do that, they are built to put minimum force on the sealing surface.
You have seen those seals that have a coil spring squeezing them around the moving part. The tighter that spring squeezes, the more pressure they can stand.
But, the faster they wear.
Since a properly vented rear end should produce no pressure, you could get away with just a felt wiper of some kind, and some older seals did just that.
So, the seals in your rear end not only do not withstand much pressure, they are built to keep oil in not water out.
Water produces pressure as you get deeper and deeper.
At 2 feet of depth, it puts almost a pound per square in on that seal. (.91psi)
Even at a foot, it puts almost a half pound. (.45psi)
Most seals will let some water by under those conditions. I have seen some tricks people who regularly drive in really deep water do to try to stop that.
Few of them work well.
I have seen people modify their housings to let them put a second seal on facing the other way. Some housings will let you do that without mods.
It sometimes helps, sometimes causes oil leaks because the original seal is not in the right place.
Every so often someone dreams up the idea of putting slight pressure in the rear end to match the outside pressure of the water.
It almost always makes things lots worse. If you could exactly match the pressure, it would work. But that is almost impossible to do if the truck is moving, since the depth changes so fast.
If the pressure inside is higher, then the air will bubble out around the seal. When the air lifts the seal slightly to let the bubble out, water comes in around the bubble.
Basically, don't worry too much about the water. As long as the truck does not sit too long with the water in and rust up the gears, it does not do as much damage as you would expect.
My old Jeep would drain out as much as a pint of clear water from the front and rear end every year after the camp, and I never did any internal work on them in over 20 years of driving it.
And in those cases, the water would stay in there for the entire hunting season.
I was changing the oil in all the gear boxes of my Jeep one year at a friend's grease rack.
Baitfish2 had a Jeep too, and was helping me.
He asked why I was doing that, when he had not changed the oil in his Jeep in years.
When he saw the water coming out, he decided to try his Jeep.
We got NO oil out of his transmission, only water. After a few minutes of waiting, a few drops of sludge dripped out the drain plug.
And he had been driving it a lot.
Was full to the proper level with water instead of oil though.......
Just keep an eye out for leaks, and change the oil regularly and it should be fine.
J
I used to have to do a lot of editing before to make the sentences line up right.
We had flooding at my hunt camp this year due to all the rains in Georgia. Normally we will pull out if its going real high, but this year it was predicted to not get too high and not last long.
So, we left our campers and several trucks in there along with some folks who wanted to tough it out. The water quickly went over the access road to a depth of several feet like it always does, and the power went off.
The folks in there had a genset, and plenty of food and water.
Plus a boat and cell phones.
I made a couple of supply runs for them. Meeting the boat at the water's edge.
Then the rains came. Finally the water got so high at the camp, they moved all the campers, trucks and equipment to the highest point and came out.
When the water went down, we drove in and looked for damage.
We had picked that place because it almost never floods, plus we had built it up some with loads of dirt many years ago. As a result, none of the equipment was damaged. The water never even got to the bottom of the hubcaps on any of the trailers or trucks.
We moved the trailers back and continued on.
The water level on the main road varied up and down. Some of us drove through it fairly deep. I advised everyone to check the oil in their diffs for water contamination.
One of my friends, took his 4 wheeler home on a small trailer when the season was winding down. After he got home, about 200 miles away, he found oil on his trailer and back truck tailgate. It appeared to be coming from the front main seal on his rear diff.
He drove through water up to the doors in his 2010 Chevy 4wd.
He wrote to ask me what he should do.
I won't post all the back and forth stuff, but basically I advised him to check for water, check for looseness in the input shaft, and make sure the vent tube was not hanging down or kinked.
He said that the vent tube was fine, and was hooked to the vent for his gas tank. The oil in the rear end was low and suspicious looking.
I told him to change it and put in a synthetic. He did, and said that it looked "grayish". After doing that, he has driven it a few times and has heard no bad sounds, nor seen any leaks.
He is still a little concerned, and wrote me the following E-Mail this morning. Below it is my reply. I welcome any comments or recommendations as to what I did or did not say.
Bearing in mind, he is something of a novice at this. He has some mechanical ability, but not a lot of off-road experience.
Here is his question:
-----------------------------------------------------------------------------------------------------------------------------
J, since the vent tube goes all the way up to the gas filler cap, I can't figure how water may have gotten in there. How the water got in is still bugging me. Is there something else I should look for ?
----------------------------------------------------------------------------------------------------------------------------
And here is my answer:
----------------------------------------------------------------------------------------------------------------------------
Not really. Water rarely gets into a rear end through the vent tube anymore. Some of the older trucks did not have vent tubes, just a small vent cap.
My Jeep had that.
When they first started putting tubes on trucks, they often did not put them high enough. But after enough people added extensions and moved the tubes higher, the companies learned.
My main worry on your vent tube was a blockage that would cause pressure to build up and force the oil out around the seal.
I'm sure the water got in the same way it always does. Through the front seal and the wheel seals.
They are designed to resist pressure and leaks from inside, not outside. Plus they are designed to last a long time.
To do that, they are built to put minimum force on the sealing surface.
You have seen those seals that have a coil spring squeezing them around the moving part. The tighter that spring squeezes, the more pressure they can stand.
But, the faster they wear.
Since a properly vented rear end should produce no pressure, you could get away with just a felt wiper of some kind, and some older seals did just that.
So, the seals in your rear end not only do not withstand much pressure, they are built to keep oil in not water out.
Water produces pressure as you get deeper and deeper.
At 2 feet of depth, it puts almost a pound per square in on that seal. (.91psi)
Even at a foot, it puts almost a half pound. (.45psi)
Most seals will let some water by under those conditions. I have seen some tricks people who regularly drive in really deep water do to try to stop that.
Few of them work well.
I have seen people modify their housings to let them put a second seal on facing the other way. Some housings will let you do that without mods.
It sometimes helps, sometimes causes oil leaks because the original seal is not in the right place.
Every so often someone dreams up the idea of putting slight pressure in the rear end to match the outside pressure of the water.
It almost always makes things lots worse. If you could exactly match the pressure, it would work. But that is almost impossible to do if the truck is moving, since the depth changes so fast.
If the pressure inside is higher, then the air will bubble out around the seal. When the air lifts the seal slightly to let the bubble out, water comes in around the bubble.
Basically, don't worry too much about the water. As long as the truck does not sit too long with the water in and rust up the gears, it does not do as much damage as you would expect.
My old Jeep would drain out as much as a pint of clear water from the front and rear end every year after the camp, and I never did any internal work on them in over 20 years of driving it.
And in those cases, the water would stay in there for the entire hunting season.
I was changing the oil in all the gear boxes of my Jeep one year at a friend's grease rack.
Baitfish2 had a Jeep too, and was helping me.
He asked why I was doing that, when he had not changed the oil in his Jeep in years.
When he saw the water coming out, he decided to try his Jeep.
We got NO oil out of his transmission, only water. After a few minutes of waiting, a few drops of sludge dripped out the drain plug.
And he had been driving it a lot.
Was full to the proper level with water instead of oil though.......
Just keep an eye out for leaks, and change the oil regularly and it should be fine.
J
