"Water Tight Drivetrain" - Does the 4R have?

[CJ3Flyr]

In addition to the rear axle vent the only 'weakness' I have read about on the 4Runner is the idler pullys which is well documented on the 4th gens and the FJC's.

Anybody have anything else to add or they are suspect of?

 

[harper7]

Since someone here already has doen the leg work.. what parts did you buy and where to do the breather mod?

I'm interested in going the route of adding the breather end under the air filter in the airbox. that places it high and protected.

- 20ft rubber fuel line
- fuel line barb for rear diff (part? cost?)
- Barb adapter to connect to breather (female/female adapter and a 90 degree barb?)
- rubber lined hose clamps to mount to factory frame rail points.
- hand full of black zipties.

Has anyone rerouted the remaining breathers and tied them all into a single line?

Okki

Here is an excellent write up by jgedmund in our 5th mods sticky. That's how I did mine except went up along the frame ,then just under the fuel door opening and did'nt cut a hole thru.Imagine about 2-3 inches shorter then his pic and on the other side of the rubber . http://www.toyota-4runner.org/5th-g...unner-modifications-write-ups.html#post528748

One thing to really watch out for running these lines up front is there are alot of moving and hot parts up underneath and the rear axle flexes up and down quite a bit. You have to leave just the right amount of slack in the breather line and be very careful where you run it.If you rub or burn a hole in the breather line it will let water and dirt directly into your rear diff and destroy it.

 

[dron]

Bingo!

...One thing to really watch out for running these lines up front is there are alot of moving and hot parts up underneath ... If you rub or burn a hole in the breather line it will let water and dirt directly into your rear diff and destroy it.

Isn't this a reason why Toyota left this only breather not exteded way up?:jump:

BTW, where is e-locker breather located? Search all feasible things underneath the car, and still no clue.:shrug:

Also, in an engine bay I can see only two breather hoses showing up on the left side of the fuse box. It should be three AFAIAC - front diff, tranny and x-case. Are any two of them tee-ed at a factory?

 

[gm350reratliff]

I ran mine just like how harper7 described. If I remember correctly I placed mine a little higher than the fuel neck cup. If the water is that high I'm screwed anyway.

As for "water tight drivetrain" I would say the 4runners are probably just as water tight if not better. This is also dependent on how fast you hit the water.

 

[iDRiVaT4R]

That's a great spot... went camping out there last memorial day, but didn't have the balls to go past that deep part of running water you are referring too. I took a hike up there and it's got a long rocky hill to climb after that which looks like fun. Maybe I'll try it in my new 4Runner, but I guess I'd need to modify the breather from what I've read around here. Hopefully it's not too hard to do...

Last time I was at Coyote Canyon was I think a week before I bought the 4Runner and If I remember correctly the water was at least 2 feet deep. I had performed the diff breather mod on the Tacoma near the end of last year. When I put the Tacoma up for sale, I just removed the breather mod stuff and put the stock breather cap back on.

This was the last trip I did with the Tacoma, going up Coyote Canyon, past the stream, up that very Rocky trail your referring to and all the way to the end. Then we had to turn around and head back. It's a very fun trail.

My mom let my 15 year old brother drive my old 88 4Runner up that rocky hill, its hers currently, and right at the top of it he drove up on the left boulder a little too far and almost rolled it. It was a little scary since I was standing on the boulders just to the right of it.

 

[SeattleMike]

Just a quick note on this: I tried to get confirmation from Toyota months ago regarding the fording depth (specifically it being the same as the FJC) and they told me that there was no information on that. I'll try and hunt down the specific thread I posted the response in, but I certainly wouldn't assume the FJC and the 4R share the same spec because their isn't any evidence that it's true.

 

[hbrunner]

There are two breathers in the engine compartment just to the left rear side of the battery. One is attached to a small hose and the other to a larger one. The small one is in the back of the larger one. Both are attached together by a clip. The small one in the back is spring loaded and moves up and down with finger pressure. The one in the front does not move. It seems it is stuck in the down position? What do you see on yours? Mine is a Trail with KDSS.

 

[polycrack]

diff mod

isn't the upside down cup on the breather just fine? I would think that when you go in watter the watter wouldn't go up the cup because it's like putting a glass upside down in the sink w watter. as long as the axel seals and diff seals were good. if you blew in the breather tube simulating watter you would just commpess the air a little or blow gear oil out one of the seals if you had a week seal. im just thinking it's good the way it is cuz you'll never be so deep that the watter pressure could compress the little air inside to enter the diff. just something to talk about, let me know what you think. ps has anyone pulled the diff and found watter?

 

[dron]

Where is the third breather????

There are two breathers in the engine compartment just to the left rear side of the battery. One is attached to a small hose and the other to a larger one. The small one is in the back of the larger one. Both are attached together by a clip. The small one in the back is spring loaded and moves up and down with finger pressure. The one in the front does not move. It seems it is stuck in the down position? What do you see on yours? Mine is a Trail with KDSS.

I have exactly same situation as you have described. Cap on a large hose isn't moving at all, but I don't think it is stuck. Probably it is how supposed to be.

But where is the third breather assuming one for diff, one for tranny and one for x-case?

 

[Titanpat57]

I have a really stoopid question...

if you entered the water slowly, and allow the rear end to cool for a few moments before forging ahead deeper...wouldn't this allow the the two (water temp and rear end temp) equalize enought o make this a non-issue?

just curious..thanks in advance

Pat

 

[snow&surf]

Here is an excellent write up by jgedmund in our 5th mods sticky. That's how I did mine except went up along the frame ,then just under the fuel door opening and did'nt cut a hole thru.

How many feet of tubing is required with the breather in this position? I plan to run it up into to OEM tire jack storage area and figure this would be the same place as yours which would require the same length of tubing.

 

[dron]

I have a really stoopid question...

if you entered the water slowly, and allow the rear end to cool for a few moments before forging ahead deeper...wouldn't this allow the the two (water temp and rear end temp) equalize enought o make this a non-issue?

just curious..thanks in advance

Pat

I've asked this question few times in a different way - why on the earth Toyota (and many other 4x4s) cares only about front end of a truck by extending dif and tranny breathers up to an engine bay, but doesn't do so for the rear diff????

Anyway, looking at the breather construction (whatever is available on the internet), at no circumstances water can enter differential - it works one way to relieve pressure, unless the breather complete malfunction. This can happen if breather corroded to through holes. It is hypotized also that mud can get breather clogged but that will seal this thing even better. But this is still no hope to answer the first question.

I know, people will say about cheap insurance, 15 mins work and "every serious off-roader does that" - I am still not convinced

 

[Underoath]

I have exactly same situation as you have described. Cap on a large hose isn't moving at all, but I don't think it is stuck. Probably it is how supposed to be.

But where is the third breather assuming one for diff, one for tranny and one for x-case?

Well when I had my FJ assuming it is in the same spot as my 4 runner, If you looked down between the firewall and the mid rear portion of the engine you could actually see the 3rd breather, which I think was either the tranny or x case breather.

 

[harper7]

How many feet of tubing is required with the breather in this position? I plan to run it up into to OEM tire jack storage area and figure this would be the same place as yours which would require the same length of tubing.

Been awhile but pretty sure I bought 5 feet of 3/8" ID fuel line.

Where mine ends is behind that flap in the rear of the drivers rear wheel well and zip tied to the filler neck on the inside leaving slack for rear axle flex from the diff of course.

I measured it yesterday and it was at 44 inches high which is over half way up the doors.Water getting in my rear diff will probably be the least of my worries if I'm in water that deep.

 

[harper7]

I've asked this question few times in a different way - why on the earth Toyota (and many other 4x4s) cares only about front end of a truck by extending dif and tranny breathers up to an engine bay, but doesn't do so for the rear diff????

Anyway, looking at the breather construction (whatever is available on the internet), at no circumstances water can enter differential - it works one way to relieve pressure, unless the breather complete malfunction. This can happen if breather corroded to through holes. It is hypotized also that mud can get breather clogged but that will seal this thing even better. But this is still no hope to answer the first question.

I know, people will say about cheap insurance, 15 mins work and "every serious off-roader does that" - I am still not convinced

You can lead a Diff to water but you can't make him drink!!lol http://www.toyota-4runner.org/5th-gen-t4rs/72639-rear-diff-breather-annoyance.html#post619739