My Differential Breather Mod Photos

The problem with check valves is they get gcrapped up and don't seal or else close and don't open. Its just a spring loaded valve. I had one goobered up in my NISMO Frontier (salt and snow crud over a few seasons)and it caused the axel seal to leak out onto rear brake on driver side when I was towing a load (heated up and expanded in there). Nissan wanted to replace seals and brakes (900$) but my mechanic said we should try to clean out valve and clean up the brake/wheel. In his experience the seals on the Frontiers can reseal once the pressure is relieved in pumpkin. It worked in this case ($100) and stopped leaking at the seal, but brake pad was ruined (soaked diff oil in, this did not clean up). I am putting the extended axel vent you guys worked out on my new Tacoma Sport this weekend (traded the 05 NISMO). Cheers!

 

why didnt you just pop that cap off that plug and save a few bucks i did mine with a npair of pliers then put the hose and clamp on

 

I thought the Nissan axel seal was shot since it had leaked considerable oil into the wheel, didn't realize the breather design was so problematic. . Took it to a local mechanic who told me the seal may be fine if you clean up or replace the breather valve, no garauntees but in this case the seal held once the breather was working again.

I put the vent on my Tacoma this morning and had some pressure in the pumpkin when I loosened the stock breather (pumpkin was room temp from sitting overnight in garage). Surprised me. I wouldn't expect that it should be running with any pressure. Brand new 2011 truck, 1200 miles. Wat's up with that??

 

I believe it was negative pressure (at least it was with mine). The valve is designed to let pressure out but when the diff cools down, no air can come in past the axle vent due to the spring/gasket design. That's the whole reason for the mod though, so it's a good thing that you got it done!

 

I looked at the same thing but decided not to do it because the leftover piece is small and the diameter is pretty big - you'd need a monster hose and don't have a lot of room to attach it to the nub that's leftover after you disassemble the valve.

The replacement part has a barb. After attaching a hose clamp there's very little chance (if any) that the hose will come off.

 

Because using the right part is the right thing to do... and it was like $5, so contaminating the differential if the hose falls off the modified breather is not saving anything. The right part (union) has a barbed insert end to help secure the tube.

 

Nice! Doin mine next week

 

I did this mod with a slight twist.

First, let me say that my Taco is my daily driver. I have taken it off-roading a little bit, but nothing major - I have a trail rig for that. I did this mod because I don't like the idea of the sealed pumpkin and its inability to inhale while it cools. Plus, the little breather could get gunked up and stop working altogether.

The first part where I varied from the OP is that I used an inexpensive fuel filter instead of the barbed OEM type breather. I got the fuel filter from O'Reilly Auto parts for $2.47. There were 2 options; this one was more reasonably sized - it almost looks like it was made for lawn equipment.

The other variation is in the mounting location. I ran the hose up into the fender well (like in another thread on the same subject) but I used an insulated band clamp and a bolt/wingnut to secure the hose. This way I don't have to see the breather or be concerned about losing any space in the bed cubby and all that's visible is a bolt head behind the gas fill door.

 

Very cool... is there much restriction when you blow through the filter in either direction?

 

I can't blow through it without detecting some restriction but it's to be expected since it's a filter. In no way do I think it's over restrictive or will prevent the diff from getting adequate ventilation. It's way better than the OEM version for breathability...

ADD: Plus, trying to blow through a straw, even without a filter, is going to give you the sense that there's some restriction when in fact there isn't.

 

10-4... given that the stock breather is not a breather at all... only a spring loaded outlet vent... it should be better.

With this mod., we are installing the SAME breather Toyota puts on the FRONT differential... which already is elevated at the end of a hose. IT JUST MAKES SENSE that the back differential on all 4WDs should get the SAME treatment, right???

 

Equal rights for front and back diffs!

 

YAH!!!

 

Bump... Have you all done this mod yet? It's the rainy season here in the west!

 

The front isn't so hot either. I just got a front seal replaced (under warranty, as was the heater blower fan), and they told me the front diff was full of water. While this summer was a wet one, I've only once in 25k miles driven in water to roughly the middle of the wheels, and this only briefly.

Where else could the water have come from?

 

I would say that was a BS story... anyone who finds a diff. full of water would make a pretty big deal out of it, and a responsible service writer would find the cause ASAP... not let you drive away. They are basically saying you drove the truck into a lake up to the hood (so the elevated front breather would allow water in...??? The truck is new, so waht did they do?

 

They changed the leaky seal under warranty, and charged me $30 for a diff lube change, which was called for at 35K miles.

 

If the seal was due to warranty the fluid change which is required with the seal change should have been covered.

 

Any "official" reference to this? Before I go back and chew them out, I'd like to make sure...

 

Well, similar but not equal...........they certainly replaced my rear brake shoes free when they ignored my first notification that the rear axle seals appeared to be starting to leak. Shortly thereafter when the fluid began being slung onto the rims and they could no longer deny the seals were leaking, they had to replace a non-warranty item due to the warrantied parts crapping on them. Should be same thing for you, the warrantied item failure caused contamination to the fluid (non-warrantied wear item). Just like my story so try to make them reimbusre you or change the fluid in the rear axle for free so both are fresh.