Ventilation valves - More than expected!

Okay I know about the rear differential vent valve and extending its length. I know of the front differential vent valve thanks to Amazon after being unable to find anything on this creature in the FSM. Quite possibly I don't know the name that Toyota uses for it which has hindered my search.

Getting to the point, is there such a valve for the transmission? If so, I would guess that it and the front diff valve need extending as well?

 

There are 3 in the engine bay. The shiny one (pictured) next to the other one is just like the rear diff one I replaced. I believe its the same part number IIRC and it was partially stuck so it was replaced, too. They look and have the same action (out only one way).

The one next to it is skinny and is open to both in and out (saw no need to replace it). The one behind the manifold is I believe an in and out as well. Its difficult to access and so I twirled it and it feels like its just hard plastic with a fixed cap with no spring action.

There is another (transfer case?) breather directly on top of the transfer case. Its screwed right into the top. You’ll need gorilla arms to reach it and spin it. It feels spring loaded and the action was bouncy so I feel its good to go. Not sure how one would replace it, unless the trans is dropped.

 

Thank you Fred for the over-the-top thoroughness of your answer!

 

An unrelated comment...Those Denso coil packs sure look sweet. [envy] After 17 years, mine should probably be replaced, but man they can kill an austere budget.

 

Thank you. The originals were on their way out. Half were cracked and I had one replaced after the only time the truck ever had a malfunction where she limped home on 7 cylinders which was about 2 years before joining this site.

Careful study on Amazon found these Densos. The reviewers mostly all went the cheap Chinese route first before coming around to these. I learned from their mistakes and bit the bullet to the tune of $450. So far so good.

I still have the one no brand replacement and 3 others OEM in fair condition that I’m keeping just in case. The other 4 are cracked, but still working. I tried selling them for around $10 each last year here and on Facebutt Market with no takers.

 

I've listened and learned - Aisin water pump, Denso coil packs and Toyota ball joints - accept NO substitutions! I have nothing that points to any earlier failures in these item's past and consider a 17 year run a testament to their quality and longevity. Sometimes one needs to step up to find true value.

[edit] Correction, make that an 18 year run after passing her anniversary date and model year debut.

 

The one next to the your shiny one goes to the front diff ADD actuator. Are you sure it's two way? Mine holds a vacuum, but it is pretty crusty. When I yanked on it, it let a bit of air in, but just the one time.

Both of the front diff breathers (that terminate below the fuse box) can be extended from behind the driver shock mount where they connect to hard lines. It's a lot easier with the upper control arm taken out. The small hose is 4mm.

Regarding your last picture, do you have the push button 4wd? And what side is that picture taken from? It seems like mine just has a hose that runs from the passenger side of the transfer case cover (where the shifter would go) and runs a few inches forward to between the transmission and the transfer case. The transfer case actuator hose goes to the same general area, just on the other side. Post #7 on says that dead space is where the transfer case vents in Tacomas and 4Runners so it makes sense. But I'm not sure how that area vents.. Is it through the transmission breather in the bell housing?

 

Looks like post #2 answers my questions and shows that short hose. I guess I'm leaving that one alone until I get enough water in it that I have to drop the transfer case haha.

 

@ds2c Very nice accompaniment to Freds comments and pics, and it will be well received by the membership, I am sure. Thank you for the submission and link.

 

I was somewhat surprised the other day when changing my plugs on my 2004 188K miles. They all looked in very good shape physically and chose to purchase only 1 from the dealer the other day just in case.

 

The one you are saying goes to the front ADD actuator: I wasn’t sure where it went which is why I put a question mark. I did remove it and its a skinny posted plastic type breather. I cleaned it and tested it both ways using lung power. Seemed good to go.

Yes on the push button 4WD. That picture was taken while laying under the truck at its midpoint with my arm extended up between the muffler and transfer. I had to use Crane Technique with the phone in my hand while snapping the picture by feel one handed. Not much room up there between the top of transfer and bottom of cab. Or maybe this is the back end of the transmission case area?

 

Thanks for this link to this photo. I circled in red the breather that ‘few have seen!’.

I often wondered, with all the paranoia about breather extensions in the 4WD community, why nobody talked about this one. Seems very vulnerable in water crossings.

 

I think the coil packs last longer (or indefinitely) as long as you keep your spark plugs changed at their required intervals. In my case, I let the plugs go longer than they were designed and my PCV was plugged up for years causing the engine to run hotter leading to the cracking. Thats my theory anyways.

A bad plug will make the coil packs run hotter for sure.