EDIT: UPDATED WITH PICS!!
I'm going to finally practice what I preach, and extend my breathers. I've been compiling the data and here's what I have so far:
I finally got around to extending my breather tubes. I'm getting ready for the Jeep Jamboree in the Pine Barrens, NJ, and I've heard that it is VERY wet there. So, no time like the present to spend $15 in parts to save $$$$$ later!
There's a breather tube for each component. Front and rear differentials, transfer case, and in my case, auto tranny. The front diff tube comes up on the body just below the battery tray. VERY easy to get at. I brought it up to the master cylinder area.
The rear diff pokes right up through the driver's side of the rear and goes up about a foot. I brought it all the way up to the gas filler tube area.
The transfer case breather comes up along the auto tranny's dipstick tube. I'm extending that to the master cylinder area, even though it's pretty darn high already.
And finally, the controversial tranny breather. I was told by some that the breather is impossible to access with the tranny still in the jeep, and it doesn't go up high enough for most water crossings. Maybe that was the case in 2002, but in 2003, it's located on the engine block, just behind the driver's side head. you can't see it, but you can easily get at it. The engine ground strap is also mounted here, so just follow that from the fire wall down. This will be extended to the master cylinder area as well (once I buy more 5/16" fuel line because I ran out!
This is EASY to do. NO EXCUSE NOT TO DO THIS!
Here are the pics:
Front Diff:
Take a flat head screwdriver and just pop this bracket off of the bolt under the battery tray area. This round bracket makes it easy to zip-tie the breather in place later.
Rear Diff:
NOTE THE CLIP JUST ABOVE MY FINGERS. I pulled the stock clip off with the tube and used it on the Kilby Tank skid to keep the tube away from the springs, and to also allow enough slack for the rear axle to flex without pulling the tube loose.
Diff Breather along tranny fill tube:
EDIT: UPDATE FROM GARRY:
A KJ friend of ours just had his breathers extended while the KJ was in the shop. He had a GREAT idea that I promised to share here.
He extended the breathers all the way to the airbox. First he merged the lines, then ran only one tube into the box and sealed it up nice and tight. I hope to see it next month and will take pics. I assume they drilled a small hole and then siliconed around it when done.
His theory is that when he gets a snorkel, he'll be MUCH more prepared for the wet stuff.
Oh, and the mechanic used a part available for Marine applications for the end of the hose. It's some sort of end that greatly reduces the likelihood of water going down the tube, even if submerged for a short time. I'm going to check that out too!