200 Series Drivetrain Breather Project

[ttrmike]

I haven't seen to many threads here in the 200 section regarding drive train breather extensions, so I figured I might as well document my experiences for reference later. The plan is to extend the front and rear differentials, as well as the transmission and transfer case breathers into the upper engine bay. Think of this as part 1, as the transmission and transfer case breathers are more difficult to access, but more on that later. Contrasting to previous breather projects, I decided against terminating all the lines to a separate barbed fuel filter, or connecting everything in line before the engine bay. This might not be The way, but its a way.

Parts list:
25ft 1/4in ID fuel line
X4 5/8in stainless hose clamps
X1 Hitachi 1/4in NPT 4 port air manifold
X5 1/4in NPT to 1/4in barb fittings (F/R diff, Transmission 1&2, T/C)
X1 1/4in NPT to 1/2in barb fitting
X1 Crankcase filter (1/2in inlet)
Scrap steel flat bar
Misc Toyota hardware (M8, M6)

Here's the breather manifold mocked up, and labeled.

Drilled the top of the manifold M6x1.0 for mounting.

Bent some scrap 1/2inx1/16in steel to mount in front of the brake booster.

Breather manifold mounted.

OEM rear differential breather mounted just in front of the spare on the frame. Lots of escaping air when i pulled off the hose, but that's to be expected on a cold diff. The factory bracket used to hold the OEM breather to the frame is also spot welded together, so i drilled the spot weld and repainted the bracket to reuse it with the new breather hose. I routed the hose along driver side with the various AC, fuel, and wire looms that run underneath the LC. I made sure near the engine bay that the hose was well out of the way of the heat from the cat as i ran the breather to towards the brake booster. I ran a total of 158in of 1/4in fuel hose from the rear diff up to the breather manifold.

Continued on second post.

 

[ttrmike]

The front breather is much faster process. The OEM breather ends just below the brake booster.

The hose is only about 6in long, so if you look behind the plastic cover in the drivers side wheel well you’ll find the hard line from the differential. I added about 40in of fuel hose, and routed the new line through the same OEM clip that retained the original hose.

Now the hardest part was trying to locate the transmission and transfer case breathers. There a lot of stuff going on underneath the 200 series, so if took a minute to locate everything. The parts diagrams helped confirm that they were actually there. Both the transfer case and the transmission begin on the drivers side, and then travel over the top of the transmission, and end on the passenger side the cylinder head. Most of my research for these breathers was actually from the 100 series section, and fortunately it’s similar. Unfortunately, these seem much more difficult to access than their 100 series counterpart. Where the 100 series had a front and rear transmission breather, the AB60F has only one located towards the rear of the housing. The transfer case for the 100 has two breathers, while the 200 has three, but they all seem to be T’d together before going up to the firewall.

Continued on next post.

 

[ttrmike]

So for now, this is just a differential breather project. But I’m going to reattempt the other two breathers later. Part 2 to follow.

Overall it wasn’t a difficult job and it offers some piece of mind in the inevitably flooded PNW trails.

 

[grinchy]

Nice project

 

[Eisbaer]

Subscribed. Interested in part 2.
Short of installing a Snorkel, I assume this would the next best upgrade to handle deep water. Or are there other ideas?

 

[ckkone]

I’ve seen something similar to this available commercially that uses pneumatic air exhaust breathers. I like the DIY effort, nice job.

 

[kcjaz]

So for now, this is just a differential breather project. But I’m going to reattempt the other two breathers later. Part 2 to follow.
View attachment 1907026

Overall it wasn’t a difficult job and it offers some piece of mind in the inevitably flooded PNW trails.

Did you finish this project? I'm currently trying to figure out how to get to the tranny/transfer breathers.

 

[ttrmike]

Did you finish this project? I'm currently trying to figure out how to get to the tranny/transfer breathers.

Unfortunately I never took any photos for part 2.

I did however successfully extend the two transfer case and one transmission breathers to the same manifold. The three breathers are several inches below the top of the manifold, at the center rear of the engine. If you remove the engine cover and lay on the top of the engine looking down between the intake and firewall you'll find the three breathers linked together. Honestly it's a job best completed when the intake manifold is removed (valley leak fix time) for the sake of access.

Of the three lines, two were compatible with the 1/4 double sided barb splice.

One line was closer to a 4(?)mm and I used a 3/16(?) to 1/4in barb splice adapter. I dont recall the exact measurement, but the one line is a smaller diameter hose.

 

[kcjaz]

Unfortunately I never took any photos for part 2.

I did however successfully extend the two transfer case and one transmission breathers to the same manifold. The three breathers are several inches below the top of the manifold, at the center rear of the engine. If you remove the engine cover and lay on the top of the engine looking down between the intake and firewall you'll find the three breathers linked together. Honestly it's a job best completed when the intake manifold is removed (valley leak fix time) for the sake of access.

Of the three lines, two were compatible with the 1/4 double sided barb splice.

One line was closer to a 4(?)mm and I used a 3/16(?) to 1/4in barb splice adapter. I dont recall the exact measurement, but the one line is a smaller diameter hose.

Thanks. After seeing this pic from @sdnative posted I was hoping I could get to them from the top but after climbing in my engine bay I can’t even see them let alone get my hands down to them. I don’t really want to remove the intake just to get to the breathers.

 

[sdnative]

Really not worth it IMO unless you are fixing a valley plate leak and have the intake and SAIS valves off.

 

[AnyMal]

Really thorough job here but it has hate my life written all over it.
Would it be okay to just barb couple the existing bobs and extend?

Thats also a nice little junction block up there from PDP I didn't know existed.
Bookmarked.