3rd Gen Tundra Diff Breather/Axle Vent

I read on here about the rear diff on the 3rd gen Tundras being a simple vent on top of the differential, and I was able to locate it on my truck and and will be relocating it to a higher position. My question is about the front differential. Does the front differential breather have a hose relocating it up higher than the top of the diff? Does it even have a breather? I can't seem to find any information about the front diff breather online. I am hoping that someone has investigated this on their pickup. I would go look at mine real quick, but with the skid plates it is hard to get in there to investigate it.

 

No real need to do anything up front. The breather is extended and mounts up a bit higher on the body.

 

That is great info, thank you! Interesting that they would extend the front breather up but not do the same with the rear.

 

Can you please post some pics after you extend the rear diff breather ? Thank you.

 

Here’s a few pics for this kit that extends it behind the brake light.
https://irontrussfabrication.com/products/2022-rear-differential-breather-relocation-kit

 

I sent mine straight up with some 5/16 fuel line and Toyota union

$8 90404-51319 Toyota Union - 90404-51319

90404-51319. I may reline it and send it like the above post

 

Thank you very much guys

 

Yeah I'll see what kind of pics I can get when I do it. I pulled the factory breather off and measured the threads and it appears that it is 1/8-28tpi BSP threads. I initially thought it might be 1/8-27tpi NPT threads but it was not. I can post the components that I used once I complete it.

 

I got the diff breather relocated finally. I'll post links to the products that I used. I ordered the hose barb with 1/8 BSP threads off of Amazon because I could not find one locally, due to the BSP threads. The hose barb at the axle is for 1/4" hose and the breather has a 5/16" hose barb, so I got an adapter. I ran 1/4" fuel hose from the axle to the adapter right near the breather, but then I added the adapter to transition from 1/4" to 5/16" right before the breather. If you can find an 1/8-28tpi BSP fitting with a 5/16" hose barb that would be ideal, and could avoid the need for the adapter. But this should work fine.

1. 1/8-28tpi BSP hose barb:

$7 EDGE INDUSTRIAL 1/4" Hose ID to 1/8" Male BSP BSPT Straight Brass Fitting Fuel / AIR / Water / Oil / Gas / WOG (Qty 01)

https://www.amazon.com/dp/B07CX58JBP?ref=ppx_yo2ov_dt_b_product_details&th=1
2. Breather:

$5 Differential Vent Breather

https://www.amazon.com/dp/B06XHBY38X?ref=ppx_yo2ov_dt_b_product_details&th=1
3. 1/4" to 5/16" hose barb adapter:

$7 Beduan Brass Hose Barb Reducer, 5/16" to 1/4" Barb Hose ID, Reducing Barb Brabed Fitting Splicer Mender Union Air Water Fuel

https://www.amazon.com/dp/B07PMQDLZ6?ref=ppx_yo2ov_dt_b_product_details
4. 10 ft of 1/4" low pressure fuel hose. I used just over 8 ft of it.
5. Hose clamps (I had a random assortment laying around).
*EDIT - 6. Short length of 5/16" fuel hose.

Now for the pictures.

The full circuit laid out and loosely attached:

The original breather:

Now with the new hose barb:

And with the hose attached:

The finished breather hose with slack in the line and secured to the electrical cable:

Routing it over the frame crossmember toward the rear of the truck:

And the finished breather inside the taillight opening. The picture was taken through the opening of the taillight with the light removed. I should have gotten one while standing back a bit farther.

 

thanks for the info @CORam

only place i can find 5/16 barb BSP fitting is MacMaster Carr

https://www.mcmaster.com/catalog/130/342/1075T307
Brass Barbed Hose Fitting for Air and Water, Straight Adapter for 5/16" Hose ID x 1/8 BSPT Male
1075T307
$11.77 + $8.28 shipping
$20.76

Would be interested if anyone can find the Toyota Union, screw in barb fitting part number like we've used on previous generations 90404-51319


Edit: just get Toyota part noted by @TundraTT (sorry missed your post above) much cheaper. Anyone with previous Yota truck/suv should be familiar with this part it’s been the same for 60 years

 

Read above… same union fits

 

Interesting about the McMaster part. I originally thought that the breather was 1/4" hose and when I looked on McMaster I saw that the 1/8" BSPT x 1/4" hose barb was $20 + shipping for a pack of 10 of them, so I looked elsewhere. Now that you point that out, I would probably go with the McMaster part that you posted and then could skip the 1/4" to 5/16" hose barb adapter. That would be cleaner. Thanks for posting that.

 

TundraTT, that is good if you confirm that that Toyota union fits. I had seen that part on Amazon early on but couldn't confirm the threads on it, so again I looked somewhere else to ensure that I got the right BSP threads. And I don't think I saw the link in your post before - that would have saved me some time.

 

Thanks for the write up. Did this today with the Amazon toyota union, reused the original breather vent.

 

An interesting observation from when I relocated the breather. As I unthreaded the OEM breather from the axle there was a very distinct "pffft" sound as I got toward the final threads. Gases obviously passed by the breather as the threads opened up. I couldn't tell if the gases flowed into or out of the axle, but it is quite concerning and has me believing that the OEM breather is defective. It happened twice - once when I removed the breather to measure the threads, then I put the breather back on. Then weeks later I pulled it again to actually relocate it and it did it again. Both times the truck had been sitting in my shop for days prior without having been driven.

This came to mind as I saw that several of you on this thread re-used the OEM breather and I hope you don't have the same issues with yours. I have not opened up the new breather to check for a release of gas, but I plan to check it for the same issue at some point.

Did anyone else experience this release of gas upon removal of their OEM breather?

 

No noises when I pulled mine. Checked the OEM before putting at hose end - all good.