New 4Runner water fording height?

[TeryT]

I was looking at the rear axle on the newer 4Runners & to my surprise there is no breather tube - only a vent cap. 4Runner is supposed to be an awesome off-roader, yet the only new Toyota I see with a live axle breather tube attached is the Land Cruiser.

How's come?

What is the recommended water fording height on the new 4Runners? Is it the obligatory axle hub height? I can't see where it would be any deeper, unless on adds a different cap & breather tube.

Also, and thoughts on using a water-proof grease (like Royal Purple) on the front 4Runner hubs? I've been using it for years on my Pathfinder front hubs - no problems & 208k miles!

 

[Biff]

I was looking at the rear axle on the newer 4Runners & to my surprise there is no breather tube - only a vent cap. 4Runner is supposed to be an awesome off-roader, yet the only new Toyota I see with a live axle breather tube attached is the Land Cruiser.

How's come?

What is the recommended water fording height on the new 4Runners? Is it the obligatory axle hub height? I can't see where it would be any deeper, unless on adds a different cap & breather tube.

Also, and thoughts on using a water-proof grease (like Royal Purple) on the front 4Runner hubs? I've been using it for years on my Pathfinder front hubs - no problems & 208k miles!

Check this out. I just did it myself on my 03 4runner

Breather Mod

 

[TeryT]

Thanks - just like I thought. But it wasn't clear if the front diff, transfer case & tranny are already taken care of on the 03-04.

 

[Guest]

Yes, all the front breathers are extended. The rear isn't but the rear is not extended on alot of SUV's and trucks. They are run through deep water without problems even without a rear extension.

 

[TeryT]

Hmmm, I wonder why that is that rears run thru a lot of water without problems? Someone else mentioned that the little cap, which is supposed to be a check valve of sorts, got mud in it - it could fail.

Also, if your rear axle is heated up, when it hits cool water - wouldn't this cause the air inside to contract & therefore potentially suck water?

 

[Guest]

The breather is a loose one-way valve. If the pressure sucks in, it closes the breather. If the heat builds up, it blows out.

Is there a chance debris could block open the breather? Yes. Is it probable? No. The breather is on top of the pumpkin where there is no debris flying from tires or body and blocked by the frame cross members and underbody.

Could a rock jam it open? No. The way the breather is made the gap has a lip that makes the gap so small, the only possible thing to jam it open is debris like mud if you sunk in up to the axles.

Driving through water, the bow wave is created where most of the water is pushed by the front of the car.

If you want cheap insurance, extend the rear breather. It takes 10 minutes.
But through experience, I have found it not necessary. If I were fjording deep water on a regular basis, I would extend to be on the safe side but the rear diff is well protected as is.

 

[TeryT]

Still, it seems funny that they would put tubes in the front items, but not the rear. If there was a negative pressure in the rear end, eventually it seems it would suck water thru somewhere.

 

[Good Times]

water shouldn't get sucked in because it'll just close the cap of the breather before water is able to get in there. Pretty simple setup that works well. Although there are chances that it can fail, it is highly unlikely unless you plan to do alot of water fording.

if that is the case, extending the rear diff is always recommended. (i'd just do it regardless since this mod is one of the cheapest mods to do!)

 

[bulldog-yota]

OK Toyota claims water fording depth of 700mm on a stock 4Runner. That is 27.5" for you guys lazy to calculate, or even to make it easier a little over two feet.

As to the rear diff breather the cap seems to work well, I took it off and tested it. But I decided to do the diff breather mod anyhow, since I had recently swapped diff fluids with Mobil1 and didn't feel like experimenting.

 

[dcampen]

That is 27.5" for you guys lazy to calculate, or even to make it easier a little over two feet.

Or, to put it another way, 3 inches below the top of the stock wheels.

 

[TeryT]

Thanks! Finally some solid fording numbers! That puts it safely a little above the bottoms of the doors.

 

[bulldog-yota]

If you want more solid tech data
Check out Toyota of Aus and South Africa
toyota.com.au and toyota.co.za look at the Prado

It uses the Lexus bodystyle (so a bit more room inside), but the same platform as the 4Runner and the same tech specs. They only have the V6 and Diesel, the US was lucky enough to get the V8.

 

[Thai]

Check out this thread i made a long time ago:

http://www.toyota-4runner.org/showthread.php?s=&threadid=128

Hope this helps.

 

[T?@\7]

They only have the V6 and Diesel, the US was lucky enough to get the V8.

After driving some TurboDiesels (Hilux's, Galloper 1 &2, Mitsu Montero) in Costa Rica over the last few summers, I can honestly say that I would like the little TD motor's as an option, mostly just for kicks and modding fun I think id rather have the TD than the V6, but the V8 over the TD

 

[ldivinag]

Thanks! Finally some solid fording numbers! That puts it safely a little above the bottoms of the doors.

just look where the air intake is...

imo, that is what you should the most worried about...

you suck water there, you're day is done or have a long time to get the water out of the engine.