Rear Differential Breather Mod For Dummies

[Boyds4Runner]

Yes, install a T connector. And I like what Boyds4Runner said above about using fuel line instead. I think he meant 1/4" inside diameter fuel line, not 1/2" fuel line. Even at $1/foot it's worth it for the extra heavy duty tube. See my post on page 1 of this thread for a link to my diff & E-Locker mod thread for photos of the parts I used and where I put the T connector.

I like the location of the ARB breather filter in the engine bay over the Toyota part I used in the gas cap location.

Thanks for making me double check because I did type in the wrong hose size.

I actually used 3/8" fuel line and not 1/2". Reason being that I used the Tacoma "union" at the rear axle and a 1/4" would not fit over the end for the line. 3/8" is most likely overkill but the 1/4" line would not fit over the union.

Part number used for the union on the rear axle - 90404-51319 Rear Diff Union

I used the write up information from [MENTION=55815]Okki[/MENTION] Parts call for 3/8" fuel line but now I can't tell if maybe I used 1/2" because I couldn't get 3/8" or vice-versa.

http://www.toyota-4runner.org/5th-gen-t4rs/94578-okkis-build-thread-4.html#post1073310

In any case I now like the idea of how [MENTION=135395]NEExpo[/MENTION] used the factory E-Locker breather original breather location to tie together the axle breather tube and the E-Locker breather tube and then just have one run from there so I may be redoing my relocation but keeping it to the front.

http://www.toyota-4runner.org/5th-gen-t4rs/212480-northeast-expeditions-2016-trdpro-build-5.html#post2262614

Page 5 Post #65

 

[Saker]

Gonna tackle this within the next couple of weeks myself. I haven't had hands on the ARB kit, but for those that have, realistically is it worth it to buy both the kit and extra heavier-duty tubing / hose? I'm all about doing this the right / most durable way, I'm just thinking about the fact that with heavier duty hose there would be at least one more zip tie or hose clamp connection to possibly come loose. Thoughts?

[MENTION=120701]Cymon[/MENTION] [MENTION=103267]Saker[/MENTION] [MENTION=3442]Boyds4Runner[/MENTION]

Whatever system you decide to use, be it ARB, Differential Breather Kit - Raw Mind Engineering or pieces/parts, if using quality parts, clamps and secured properly, it has no more chance of coming loose any more than any other OEM system that is using clamps and fasteners.
Just make sure quality parts are used, period.

Hope this helps!

 

[jwkilgore]

For what it's worth, there's probably more air inside a tube this long than there is inside the entire differential. I.e., the air that passes the filter never makes it all the way back to the diff.

The purpose of this mod is to prevent sudden cooling (submerging in cold water after extended high-speed driving) from pulling a vacuum and sucking water in past the seals. Right?

What would be wrong with skipping the two-way valve altogether? Just install nn-ft of flexible tubing capped with a one-way valve. The "breathing" would be accomplished by the flexible tubing expanding and collapsing.

 

[Cymon]

For what it's worth, there's probably more air inside a tube this long than there is inside the entire differential. I.e., the air that passes the filter never makes it all the way back to the diff.

The purpose of this mod is to prevent sudden cooling (submerging in cold water after extended high-speed driving) from pulling a vacuum and sucking water in past the seals. Right?

What would be wrong with skipping the two-way valve altogether? Just install nn-ft of flexible tubing capped with a one-way valve. The "breathing" would be accomplished by the flexible tubing expanding and collapsing.

A bunch of people have done it that way, especially if you run it up to the gas tank compartment or jack compartment. Since I used a kit with the filter already included and ran it up to he engine bay I figured might as well use it as designed.

 

[Saker]

For what it's worth, there's probably more air inside a tube this long than there is inside the entire differential. I.e., the air that passes the filter never makes it all the way back to the diff.

The purpose of this mod is to prevent sudden cooling (submerging in cold water after extended high-speed driving) from pulling a vacuum and sucking water in past the seals. Right?

What would be wrong with skipping the two-way valve altogether? Just install nn-ft of flexible tubing capped with a one-way valve. The "breathing" would be accomplished by the flexible tubing expanding and collapsing.

I understand your thinking, like using the tubing itself as a type of reservoir or receiver (as in an air receiver / or vacuum receiver in this case). I guess that could be possible.
I would weigh the amount saved on just using a one way valve and not using one vs. possible damage cost to the differential.
I know which one I would choose!

oh, wait I already have chosen.

 

[Angelo]

What would be wrong with skipping the two-way valve altogether? Just install nn-ft of flexible tubing capped with a one-way valve. The "breathing" would be accomplished by the flexible tubing expanding and collapsing.

I see your point, but after repeated use of that space during the "breathing" process, couldn't a one way valve actually limit movement within the system? If the breathing was being accomplished in a truly closed system you would have the "reservoir" necessary to recorrect once temperature changes again. Maybe I'm conceptualizing wrong, but it seems like if the fluid / air is allowed to move one way it must be allowed to reverse course as dictated by the temperature / pressure / volume requirements. Or maybe real world use wouldn't ever be as extreme as to get to that level of need.

Hi, I have too much free time at work today. :wave:

 

[Saker]

The actual purpose of the mod is to keep the inside of the differential at the same atmospheric pressure of the outside, therefore no pressure increase and no vacuum increase.

 

[jpachard]

Great write up, it's posts like this that make these forums great!

 

[jwkilgore]

I see your point, but after repeated use of that space during the "breathing" process, couldn't a one way valve actually limit movement within the system? If the breathing was being accomplished in a truly closed system you would have the "reservoir" necessary to recorrect once temperature changes again. Maybe I'm conceptualizing wrong, but it seems like if the fluid / air is allowed to move one way it must be allowed to reverse course as dictated by the temperature / pressure / volume requirements. Or maybe real world use wouldn't ever be as extreme as to get to that level of need.

It would work just like the OEM configuration (one-way valve), except provide an additional air reservoir. Basically as the diff heats up under constant use/strain the air heats up and forces itself out of the system. Then as it cools down it would pull a vacuum on the tube which would partially collapse. Once you hit that maximum temperature your valve ceases to let any air past at all. As it heats up again it wouldn't force more air out of the tube, it would just re-expand it back to normal.

The advantage being that because there's more air volume, and less of the air has the temperature difference, there would be less of a vacuum in the diff itself when cool.

But the more I think about it, the less I like it. I can see problems where the tube flexing would eventually break, especially at the transition between the diff connection (forced to stay round) and the first collapse zone.

A really really long tube, like all the way to the firewall, wouldn't flex much, if any at all, but why take the risk. Just put a two-way valve and be done with it. Sorry for the hijack :tea:

 

[toyotajoe16]

Awesome writeup! I previously was going to DIY my breather, but after seeing that this has extra spots for more breathers (i.e. a front diff breather maybe?) I think I'm going to go with this one.

 

[Cymon]

Awesome writeup! I previously was going to DIY my breather, but after seeing that this has extra spots for more breathers (i.e. a front diff breather maybe?) I think I'm going to go with this one.

In the 5th gen the front differential breather is already routed up into the firewall so you probably don't need to redo that breather. But with the rear locker in the Trail Edition you could run that breather up as well. Here is s link to a thread where they did both the rear diff and rear locker.

http://www.toyota-4runner.org/5th-gen-t4rs/214695-e-locker-differential-breather-install-trail-edition.html

 

[SFL_driver]

Thank you for the write up. My ARB kit arrives on Monday. I will also have to figure something out for my e-locker.

 

[Cymon]

Thank you for the write up. My ARB kit arrives on Monday. I will also have to figure something out for my e-locker.

Glad it can help...here is a thread with how to do the e-locker. The last couple pages is on how to to connect the ARB kit to it. [MENTION=95618]ADKexplorer[/MENTION] just did what you're looking to do a couple of weeks ago so I'm sure you could PM him as well although it is explained it in this link.

http://www.toyota-4runner.org/5th-gen-t4rs/214695-e-locker-differential-breather-install-trail-edition-7.html

On a second note I see you're in Fort Lauderdale (I'm in Hollywood). The Florida 4runners group is meeting up at Lazy Springs next weekend, the 21st for some off roading. Here is a link to the group if you have Facebook. There are some other members down here in South Florida who will meeting up near the I75 toll road and caravanning across.

https://www.facebook.com/groups/Florida4runners/

 

[SFL_driver]

Glad it can help...here is a thread with how to do the e-locker. The last couple pages is on how to to connect the ARB kit to it. [MENTION=95618]ADKexplorer[/MENTION] just did what you're looking to do a couple of weeks ago so I'm sure you could PM him as well although it is explained it in this link.

http://www.toyota-4runner.org/5th-g...rential-breather-install-trail-edition-7.html

On a second note I see you're in Fort Lauderdale (I'm in Hollywood). The Florida 4runners group is meeting up at Lazy Springs next weekend, the 21st for some off roading. Here is a link to the group if you have Facebook. There are some other members down here in South Florida who will meeting up near the I75 toll road and caravanning across.

https://www.facebook.com/groups/Florida4runners/

Thanks for the invite Cymon. I just joined the group. Unfortunately I will be out of town next weekend. I'll keep my eye on the FB page for upcoming events.

 

[ADK Explorer]

A friend asked if doing this mod would void the warranty. Thoughts?

 

[Dane2992]

A friend asked if doing this mod would void the warranty. Thoughts?

In theory yes it would but when you think about it. If there is ever a failure and water dirt gets in the locker or diff and you bring it to Toyota for inspection. They will say your at fault for off-roading the vehicle even tho it's basically designed that way.

 

[Cymon]

They would have to prove that installing the breather is what caused the failure. Same with lifts and everything else...all based on the Magnuson-Moss Warranty Act.

 

[Dane2992]

Very true ^^

 

[Woz1976-MT]

Learned something new...

Well, this thread is a prime example of why I come here every day -- learned something new about about the differentials and drivetrain!!

I understand the temperature and pressure changes (used to teach middle school science for a few years), but never really put it together with a vehicle's differentials.

So, I'm definitely going to be doing this mod (ARB, since I'm familiar with their off-road reputation). My questions...

1) Should this be done with the transfer case, transmission, and front differential, too?

2) I read somewhere in this post that you can use a "T" to use the same line as the rear differential with the e-locker. Considering my first question, this would lead to needing four lines to setup breathers for all components. Has anyone here done this?

Thanks for the help! (STILL anxiously awaiting my 2016 TE!)

 

[Dane2992]

Well, this thread is a prime example of why I come here every day -- learned something new about about the differentials and drivetrain!!

I understand the temperature and pressure changes (used to teach middle school science for a few years), but never really put it together with a vehicle's differentials.

So, I'm definitely going to be doing this mod (ARB, since I'm familiar with their off-road reputation). My questions...

1) Should this be done with the transfer case, transmission, and front differential, too?

2) I read somewhere in this post that you can use a "T" to use the same line as the rear differential with the e-locker. Considering my first question, this would lead to needing four lines to setup breathers for all components. Has anyone here done this?

Thanks for the help! (STILL anxiously awaiting my 2016 TE!)

So the front already has the breathers in the engine bay. It's only the rears that really need relocating.