Diff breather/vent size & removal?
Intermediate
Joined: Apr 2009
Posts: 33
Likes: 0
From: Brick,New Jersey
Breather
What I did to fix mine was pop off the top of the vent .you will find a spring and a dime size gasket like disk.I used a tire tube patch to make a new disk. I have not lost a drop since. good luck
Le Mans Master
Joined: Jun 2016
Posts: 5,414
Likes: 3,957
From: Cincinnati, OH
This is a good thread. I'll be inspecting the rubber spring/disc and either make a new disk or add a vent tube.
I've been noticing some drips and bought new axle seals...came across this thread and noticed the side of the case is wet, not just where the seal is so maybe it's coming from the vent.
I've been noticing some drips and bought new axle seals...came across this thread and noticed the side of the case is wet, not just where the seal is so maybe it's coming from the vent.
Drifting
Joined: Jan 2014
Posts: 1,285
Likes: 164
From: MA
Not sure if anyone has checked a thread I recently started on this same topic here BUT, essentially trying to determine what the easiest/best fix is. I saw some replies & read this thread in depth, but not too many recent replies. I'm fairly certain my leak is entirely the resutt of the vent failing/being blocked. I see some people have simply popped the cap off, removed the spring/disc, & reinstalled w/o it. Seems to me this would be the EASIEST fix if it works & if it doesn't cause any adverse effects.
Can anyone verify whether this is the case or not?
Can anyone verify whether this is the case or not?
Le Mans Master
Joined: Jun 2016
Posts: 5,414
Likes: 3,957
From: Cincinnati, OH
Removing the guts and reinstalling the cap is the same thing as adding a vent tube with or without a filter at the end.
Removing the guts is the cheapest option (free). Adding a tube can relocate the potential drip point where you can see it easier (IF it’s coming from tne vent in the first place).
Both methods remove the diffs ability to build any pressure whether the pressure is needed or not. I would add a tube IMO to keep any fluid from sloshing around and coming out the modified vent.
Either way, clean the whole diff then drive it and see if you can find the leak.
Removing the guts is the cheapest option (free). Adding a tube can relocate the potential drip point where you can see it easier (IF it’s coming from tne vent in the first place).
Both methods remove the diffs ability to build any pressure whether the pressure is needed or not. I would add a tube IMO to keep any fluid from sloshing around and coming out the modified vent.
Either way, clean the whole diff then drive it and see if you can find the leak.
Last edited by smitty2919; Oct 15, 2018 at 11:07 AM.
Drifting
Joined: Jan 2014
Posts: 1,285
Likes: 164
From: MA
Removing the guts and reinstalling the cap is the same thing as adding a vent tube with or without a filter at the end.
Removing the guts is the cheapest option (free). Adding a tube can relocate the potential drip point where you can see it easier (IF it’s coming from tne vent in the first place).
Both methods remove the diffs ability to build any pressure whether the pressure is needed or not. I would add a tube IMO to keep any fluid from sloshing around and coming out the modified vent.
Either way, clean the whole diff then drive it and see if you can find the leak.
Removing the guts is the cheapest option (free). Adding a tube can relocate the potential drip point where you can see it easier (IF it’s coming from tne vent in the first place).
Both methods remove the diffs ability to build any pressure whether the pressure is needed or not. I would add a tube IMO to keep any fluid from sloshing around and coming out the modified vent.
Either way, clean the whole diff then drive it and see if you can find the leak.
when I opened the fill hole for the diff there was significant pressure built up inside - was hissing well before the cap was fully unscrewed - so I'm really leaning that the vent being blocked is the main culprit in my situation. Alternatively, I think popping that open on occasion after the car has cooled off from a long and/or hard drive (or in very hot weather) is probably a good idea.
I took it to a self serve car wash bay, doused the diff/tranny/cradle area w/ degreaser & went to town on it w/ pressure washer for 5-6 mins being careful not to hit the couple electrical connections. Going to get it back up on blocks, add a bit of fluid, drive it around a bit & see if any fresh drips come, but ultimately I'm just going to plan on spending some time removing the exhaust & getting it a lot cleaner putting in the vent tube mod over the winter.
Melting Slicks
Joined: Jan 2009
Posts: 3,275
Likes: 739
From: Miami FL
...I'm fairly certain my leak is entirely the result of the vent failing/being blocked. I see some people have simply popped the cap off, removed the spring/disc, & reinstalled w/o it. Seems to me this would be the EASIEST fix if it works & if it doesn't cause any adverse effects.
Can anyone verify whether this is the case or not?
Can anyone verify whether this is the case or not?
Essentially, these were my findings:
The internal rubber seal was malformed into a concave shape, similar to a contact lens although not that bad. The new rubber seal was perfectly flat.
Perhaps making a new seal from a Teflon sheet, instead of just rubber, would be even better. This one already comes with 3M adhesive on one side to facilitate attaching it to a thin metal disc.
Last edited by GCG; Oct 15, 2018 at 01:12 PM.
Drifting
Joined: Jan 2014
Posts: 1,285
Likes: 164
From: MA
This is what I did in 2014 and I've had no problems ever since: Post 39, Post 43 and Post 44 above.
Essentially, these were my findings:
If I had to revisit this, what I would do to improve it would be to find a thin metal washer and using contact cement or something similar, glue the seal to it to avoid that it could be deformed again so it wouldn't stick to the vent seat.
Perhaps making a new seal from a Teflon sheet, instead of just rubber, would be even better. This one already comes with 3M adhesive on one side to facilitate attaching it to a thin metal disc.
Essentially, these were my findings:
If I had to revisit this, what I would do to improve it would be to find a thin metal washer and using contact cement or something similar, glue the seal to it to avoid that it could be deformed again so it wouldn't stick to the vent seat.
Perhaps making a new seal from a Teflon sheet, instead of just rubber, would be even better. This one already comes with 3M adhesive on one side to facilitate attaching it to a thin metal disc.
Why would you think modifying the disc would be a better option? Is there any downside to running it w/o the spring/disc in place, or is it just b/c that's how it was designed & you'd feel more comfortable keeping it close to the original design??
Melting Slicks
Joined: Jan 2009
Posts: 3,275
Likes: 739
From: Miami FL
Last edited by GCG; Oct 15, 2018 at 12:59 PM.
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Melting Slicks
Joined: Jan 2009
Posts: 3,275
Likes: 739
From: Miami FL
Melting Slicks
Joined: Dec 2018
Posts: 2,651
Likes: 1,386
From: Orange County, CA
I can report another success story for removing the spring-loaded vent and running a vent hose instead.
Prior to messing with the diff vent I replaced axle seals (pass-side 2x), diff side cover O-rings, and diff-to-trans O-ring. None of that cured my diff's leak... could've saved a good chunk of time had I known about the vent issue.
The diff fluid leak culminated in a little puddle on the garage floor (positive pressure inside the diff?) and a speckled rear bumper. 200 miles later and it's pleasing to see none of that so far.
EDIT: I wound up putting a new diaphragm, spring, and cap on the original vent nipple after removing the breather hose. It seemed okay for a little bit but the diff has now been leaking for a while
Guess I have the reinstall the breather hose and deal with the temporary odor in the garage.
Prior to messing with the diff vent I replaced axle seals (pass-side 2x), diff side cover O-rings, and diff-to-trans O-ring. None of that cured my diff's leak... could've saved a good chunk of time had I known about the vent issue.
The diff fluid leak culminated in a little puddle on the garage floor (positive pressure inside the diff?) and a speckled rear bumper. 200 miles later and it's pleasing to see none of that so far.
EDIT: I wound up putting a new diaphragm, spring, and cap on the original vent nipple after removing the breather hose. It seemed okay for a little bit but the diff has now been leaking for a while
Guess I have the reinstall the breather hose and deal with the temporary odor in the garage.
Last edited by MetalMan2; Nov 15, 2021 at 11:13 AM.
Advanced
Joined: Sep 2021
Posts: 59
Likes: 5
From: Charleston, WV
------Kinda tricky, beware-------
Tried this modification, wasnt so straight forward.
The problem is the nipple is 1/4" tall. This is not a normal vent nipple like old days you can attach a hose to. The hose will wiggle off eventually, the clamps just dont hold it tight at all. Big clamps, small clamps, zip ties, the nipple is too small.
What i ended up doing was crimping the cap back on it. Make sure it still wiggles and spins 360 with no resistance and cant be removed easily. Kinda tricky too. I pinched it with side cutters/dykes/wire cutters. If i had to do it over id make small slits on lower section so it would crimp a lil easier.
Tried this modification, wasnt so straight forward.
The problem is the nipple is 1/4" tall. This is not a normal vent nipple like old days you can attach a hose to. The hose will wiggle off eventually, the clamps just dont hold it tight at all. Big clamps, small clamps, zip ties, the nipple is too small.
What i ended up doing was crimping the cap back on it. Make sure it still wiggles and spins 360 with no resistance and cant be removed easily. Kinda tricky too. I pinched it with side cutters/dykes/wire cutters. If i had to do it over id make small slits on lower section so it would crimp a lil easier.
Melting Slicks
Joined: Aug 2014
Posts: 2,470
Likes: 460
From: East Windsor NJ
Melting Slicks
Joined: Dec 2018
Posts: 2,651
Likes: 1,386
From: Orange County, CA
------Kinda tricky, beware-------
Tried this modification, wasnt so straight forward.
The problem is the nipple is 1/4" tall. This is not a normal vent nipple like old days you can attach a hose to. The hose will wiggle off eventually, the clamps just dont hold it tight at all. Big clamps, small clamps, zip ties, the nipple is too small.
What i ended up doing was crimping the cap back on it. Make sure it still wiggles and spins 360 with no resistance and cant be removed easily. Kinda tricky too. I pinched it with side cutters/dykes/wire cutters. If i had to do it over id make small slits on lower section so it would crimp a lil easier.
Tried this modification, wasnt so straight forward.
The problem is the nipple is 1/4" tall. This is not a normal vent nipple like old days you can attach a hose to. The hose will wiggle off eventually, the clamps just dont hold it tight at all. Big clamps, small clamps, zip ties, the nipple is too small.
What i ended up doing was crimping the cap back on it. Make sure it still wiggles and spins 360 with no resistance and cant be removed easily. Kinda tricky too. I pinched it with side cutters/dykes/wire cutters. If i had to do it over id make small slits on lower section so it would crimp a lil easier.
Le Mans Master
Joined: Jun 2006
Posts: 6,979
Likes: 31
From: Wichita KS
Bringing this thread back from the dead as it helped me a lot, I found a dorman brand breather that acts just like the factory for $5 -
Melting Slicks
Joined: Dec 2018
Posts: 2,651
Likes: 1,386
From: Orange County, CA
Bringing this thread back from the dead as it helped me a lot, I found a dorman brand breather that acts just like the factory for $5 - Amazon.com: Dorman 924-284 Front Differential Vent Breather Compatible with Select Lexus / Toyota Models : Automotive
Le Mans Master
Joined: Jun 2006
Posts: 6,979
Likes: 31
From: Wichita KS
Thanks for sharing. Out of curiosity, what have you done with this part? Did you use a length of tubing on the factory nipple and put this part on the end, kind of like a remote breather valve? Or did you just use the cap, spring and diaphragm as replacement pieces for your factory breather valve?
