I've read of some people placing small fuel filters at the end of differential breather tubes to act as an air filter. Is this a reasonable idea?
Small fuel filter on differential breather tube
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get a motorcycle filter with either a plastic or stainless steel mesh screen. Do not use paper or sintered bronze. Sintered bronze will corrode real easy from water and get plugged. Paper will also get plugged by road dirt and moisture.
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Originally Posted By: Loobed
get a motorcycle filter with either a plastic or stainless steel mesh screen. Do not use paper or sintered bronze. Sintered bronze will corrode real easy from water and get plugged. Paper will also get plugged by road dirt and moisture.
Can you provide an example of such a filter?
get a motorcycle filter with either a plastic or stainless steel mesh screen. Do not use paper or sintered bronze. Sintered bronze will corrode real easy from water and get plugged. Paper will also get plugged by road dirt and moisture.
Can you provide an example of such a filter?
Useless thing to do.
Really useless,and potentially harmful.
The only mod to a trans or diff breather would be to extend it[ by a tube] for off road use.
Really useless,and potentially harmful.
The only mod to a trans or diff breather would be to extend it[ by a tube] for off road use.
my jeep had a ck valve when new. would let it vent but not suck in. when it broke I put a old school vw fuel filter on it. been on there 5 or so years now. I have checked it by blowing in it and it is not restricted yet
Originally Posted By: mechtech2
Useless thing to do.
Really useless,and potentially harmful.
The only mod to a trans or diff breather would be to extend it[ by a tube] for off road use.
X2. Useless. Extend it for off road use, otherwise leave it be.
Useless thing to do.
Really useless,and potentially harmful.
The only mod to a trans or diff breather would be to extend it[ by a tube] for off road use.
X2. Useless. Extend it for off road use, otherwise leave it be.
I installed a clear glass carb filter at the end of the extended breather tube on my toyota truck.
Originally Posted By: Shannow
For those that say "potentially harmful", in addition to useless.
How could it be harmful in any way, shape, or form ?
I suppose Mechtech mentioned "potential" if you installed the filter in lieu of the cap that typically goes on the end of the breather. That may let water in during water crossings if the vent isn't high enough (although I suppose it would be filtered water - LOL).
I'll stand behind my comment of it being useless though. The rate at which the diff heats and cools under typical use does not cause enough air exchange to warrant a filter (otherwise OEM's would have installed them years ago). It's simply not needed and would have no bearing on differential life. It's only when you enter water that causes the warm diff to rapidly cool making the housing negative. The typical vent cap would then close, stopping water from entering.
For those that say "potentially harmful", in addition to useless.
How could it be harmful in any way, shape, or form ?
I suppose Mechtech mentioned "potential" if you installed the filter in lieu of the cap that typically goes on the end of the breather. That may let water in during water crossings if the vent isn't high enough (although I suppose it would be filtered water - LOL).
I'll stand behind my comment of it being useless though. The rate at which the diff heats and cools under typical use does not cause enough air exchange to warrant a filter (otherwise OEM's would have installed them years ago). It's simply not needed and would have no bearing on differential life. It's only when you enter water that causes the warm diff to rapidly cool making the housing negative. The typical vent cap would then close, stopping water from entering.
Originally Posted By: Chris142
my jeep had a ck valve when new. would let it vent but not suck in. when it broke I put a old school vw fuel filter on it. been on there 5 or so years now. I have checked it by blowing in it and it is not restricted yet
Chris, are you sure the OEM was a check valve? Reason I ask is; They should be able to breathe in/out in response to heating/cooling, or you're gonna have leaks and ruptured seals.
I think the main thing is to make sure your vent hose is well secured, up as high as you can get it and it's not clogged with mud. I've seen them clumped with mud on the open end.
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
my jeep had a ck valve when new. would let it vent but not suck in. when it broke I put a old school vw fuel filter on it. been on there 5 or so years now. I have checked it by blowing in it and it is not restricted yet
Chris, are you sure the OEM was a check valve? Reason I ask is; They should be able to breathe in/out in response to heating/cooling, or you're gonna have leaks and ruptured seals.
I think the main thing is to make sure your vent hose is well secured, up as high as you can get it and it's not clogged with mud. I've seen them clumped with mud on the open end.
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
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Originally Posted By: JTK
Chris, are you sure the OEM was a check valve? Reason I ask is; They should be able to breathe in/out in response to heating/cooling, or you're gonna have leaks and ruptured seals.
I think the main thing is to make sure your vent hose is well secured, up as high as you can get it and it's not clogged with mud. I've seen them clumped with mud on the open end.
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
I'm sure Chris had a check valve. I have never seen a Jeep with any type of filter on an axle housing. The M38 / M38A1s had venting systems for deep fording though. As I stated in my previous post, the typical heating and cooling cycle of the diff does not cause enough differential pressure to close the check valve. When you submerse a hot diff in cold water, that's when the valve closes. The closing under this condition does not rupture seals or cause leaks.
Originally Posted By: JTK
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
The breather element looking plastic tip was a simple check valve(they are often white in color). The Dana 30's in both your XJ's also had one.
Chris, are you sure the OEM was a check valve? Reason I ask is; They should be able to breathe in/out in response to heating/cooling, or you're gonna have leaks and ruptured seals.
I think the main thing is to make sure your vent hose is well secured, up as high as you can get it and it's not clogged with mud. I've seen them clumped with mud on the open end.
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
I'm sure Chris had a check valve. I have never seen a Jeep with any type of filter on an axle housing. The M38 / M38A1s had venting systems for deep fording though. As I stated in my previous post, the typical heating and cooling cycle of the diff does not cause enough differential pressure to close the check valve. When you submerse a hot diff in cold water, that's when the valve closes. The closing under this condition does not rupture seals or cause leaks.
Originally Posted By: JTK
I do recall having a breather element looking plastic tip on the vent hoses of both my Jeep's rear diffs (1994 Cherokee, 1997 Wrangler). Don't recall what was on the fronts.
Joel
The breather element looking plastic tip was a simple check valve(they are often white in color). The Dana 30's in both your XJ's also had one.
Originally Posted By: Zaedock
...The Dana 30's in both your XJ's also had one.
My '97 was a TJ.
Thanks for the info.
Joel
...The Dana 30's in both your XJ's also had one.
My '97 was a TJ.
Thanks for the info.
Joel
Originally Posted By: JTK
Originally Posted By: Zaedock
...The Dana 30's in both your XJ's also had one.
My '97 was a TJ.
Thanks for the info.
Joel
Ahh, opps. No problem.
Originally Posted By: Zaedock
...The Dana 30's in both your XJ's also had one.
My '97 was a TJ.
Thanks for the info.
Joel
Ahh, opps. No problem.
Obviously harmful if it gets wet and then freezes, and stops breathing. Then, seals can leak because of increased pressure.
Harmful if the flow is not good for whatever reason , even if it is new.
And who sells a filter that fits the tiny neck of a normal breather? We'd have to cobble up an adapter.
What exact benefits would anyone think would happen?
Dirt?
I never saw dirt enter a stock capped vent in any manual or auto tranny. Water? Yes.
It all gets back to useless.
Harmful if the flow is not good for whatever reason , even if it is new.
And who sells a filter that fits the tiny neck of a normal breather? We'd have to cobble up an adapter.
What exact benefits would anyone think would happen?
Dirt?
I never saw dirt enter a stock capped vent in any manual or auto tranny. Water? Yes.
It all gets back to useless.
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This ^
Worked on a motorhome E350 that had packed dirt in the whole vent tube all the way into the housing. I was never able to figure out how that happened.
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