Hello!

[nkyrental]

New member here with a 2012 Tundra double cab, 4.6L 4x4. Like the truck a lot so far, I've had it for a few months. Do have a question though, I checked the rear differential fluid before we towed our camper to the lake, and when I removed the fill plug, there was audible pressure built up in the differential. So, I checked it a few days later and again enough pressure to hear the air loss when the fill plug was loosened. Anyone have this problem, and wouldn't constant built-up pressure cause future seal leaks? I'm wondering if there are any aftermarket differential vents to replace the 50 cent one on the diff now that would work better. Thanks in advance.

[Highwaylizard]

New member here with a 2012 Tundra double cab, 4.6L 4x4. Like the truck a lot so far, I've had it for a few months. Do have a question though, I checked the rear differential fluid before we towed our camper to the lake, and when I removed the fill plug, there was audible pressure built up in the differential. So, I checked it a few days later and again enough pressure to hear the air loss when the fill plug was loosened. Anyone have this problem, and wouldn't constant built-up pressure cause future seal leaks? I'm wondering if there are any aftermarket differential vents to replace the 50 cent one on the diff now that would work better. Thanks in advance.

Not familiar with the second generation set-up but I would be concerned about this. I had three seal failures (replete with washed out bearings and, due to some genius decisions on my half during reassembly - a new rear end) as a result of a clogged breather. I did the breather extension modification and have not had a problem since.

Welcome to the best Tundra Forum on the internet and congratulations on the best AMERICAN made truck in the world.

[Stone_Blue]

Not sure if the Nissan part would work on the Tundies, but here ya go:

Minute Mod: Differential Breather - ORN

Jackson's Rear Diff Breather

I did those mods on my 80 Toy Hilux, and one of my '88 Toy PU's.

I'll probably do it on the Tundie.

To find out if the Nissan part will work, I'll check the part number for the breather vent on an early 90's Toy PU, and compare it with one from a later Tacoma, and the Tundie to see if they are the same. If so, the Nissan part should work.

[Highwaylizard]

Not sure if the Nissan part would work on the Tundies, but here ya go:

Minute Mod: Differential Breather - ORN

Jackson's Rear Diff Breather

I did those mods on my 80 Toy Hilux, and one of my '88 Toy PU's.

I'll probably do it on the Tundie.

To find out if the Nissan part will work, I'll check the part number for the breather vent on an early 90's Toy PU, and compare it with one from a later Tacoma, and the Tundie to see if they are the same. If so, the Nissan part should work.

I just went to Auto Zone and sized up a brass fitting by eyeballing it and got lucky. You will want to go with as large a nipple (Heh heh) as possible and the largest ID tubing that will work with that nipple. I think I went with a 3/8 ID hose.

[Tones]

What you are likely hearing is a vacuum being relieved. The breather is a check valve which will relieve pressure as the diff heats up for the very reason you are concerned about. The check valve will not allow external air/water to come back in as the diff cools, creating a vacuum. Perfectly normal. You probably checked it cold? so where would the pressure come from?