Fording Heights

[Scott z]

I recently replaced my rear axle breather hose with something longer/higher and had previously added a transmission breather extension hose routed up to about 6 feet.
Planning on raising the exhaust another foot although perhaps not necessary if positive pressure is enough to keep water out.

If Axles, transmission and exhaust are routed up high, what's the next weak spot? I was guessing the batteries and battery switch/disconnect box?

Would be nice to have a better understanding of how deep is too deep. At what level are we going to damage components?

Another related question that I've never heard a satisfactory explanation for is the transmission plug bolt. We are supposed to screw in the bolt when fording but when removed, no oil drains so this seems unnecessary as related to fording. Perhaps having the bolt removed during normal conditions is important to have a place for oil to drip if something is wrong? A way to detect an internal issue that manifests itself as a drip on the ground from this unplugged plug hole?

Thanks in advance!

Scott Z.

 

[Coffey1]

Your tourqe converter may not like swimming
And water could leak through seals with that big ass converter pushing all that water at it

 

[Keith Knight]

This might be to deep!!!!

 

[Awesomeness]

Another related question that I've never heard a satisfactory explanation for is the transmission plug bolt. We are supposed to screw in the bolt when fording but when removed, no oil drains so this seems unnecessary as related to fording. Perhaps having the bolt removed during normal conditions is important to have a place for oil to drip if something is wrong? A way to detect an internal issue that manifests itself as a drip on the ground from this unplugged plug hole?

I just think it's not meant to be permanently sealed, airtight. There is a lot of thermal expansion that goes on in there, plus the possibility of fluids leaking, as you mentioned. Don't seal it unless you're fording deep water.

You're probably overthinking all of this, anyway. Are you really going to be fording that much water?

 

[Ronmar]

The bell housing has a vent port on top, passenger side, so it shouldn’t be able to build pressure. I believe it is as you assume for the drain plug. It stays out to let you know if rear main, trans input or torque converter start leaking, and goes in for fording...

lotsa vents:
front axle(which combines front hubs)
rear axle
transmission
bell-housing
all brake cans have a vent line up to frame height
fuel tank
crankcase breather hose runs down to frame height.
and I feel like I am still missing something

As you mentioned batteries. If they have vent ports these could be run upwards. Standard vented wet cells you probably wouldn’t want to submerge, AGM’s might be OK, but I wouldn’t run them under in salt water...
Don’t think I would want to run above the alt under any circumstances...

 

[Scott z]

I just think it's not meant to be permanently sealed, airtight. There is a lot of thermal expansion that goes on in there, plus the possibility of fluids leaking, as you mentioned. Don't seal it unless you're fording deep water.

You're probably overthinking all of this, anyway. Are you really going to be fording that much water?

Agreed on both. Had not considered thermal expansion. As far as overthinking fording heights I'm probably guilty as charged, however here in Houston it seems there's always going to be flooding a few times a year and I'd like to be capable of crawling through it.

That being said, the last time I drove through "deep" water...deep enough to float cars and stop everyone, I never had water above my tires and I'd guess no more than 2 1/2 feet for most of it.

 

[Awesomeness]

That being said, the last time I drove through "deep" water...deep enough to float cars and stop everyone, I never had water above my tires and I'd guess no more than 2 1/2 feet for most of it.

These trucks have ~27" of ground clearance to the bottom of lowest stuff (e.g. air tanks, gas tank), and then then some more before you get to other things (e.g. oil pan, transmission, etc.). Water that deep, if it's moving even at all, is very dangerous, you're not going to be driving through it for long hopefully.