I was looking through some writeups on extending your breather lines, and someone noted that all of the breathers (transmission, transfer case, axles) came from the factory with check valves installed on the end. Is this right? If this is right, then why is extending the breathers necessary other than to accomodate axle droop?

Micah

 

Relieve pressure build up so seals won't seep or leak, and keep water out, but I won't trust them to do it, after water still check fluids

 

I understand that the axles, transmission, and transfer case need breathers for gas expansion and ventilation. However, I can't find if there are true check valves on the ends of the breather hoses for the components. If there are check valves, it seems a vacuum would be pulled when the parts cooled down.

If there are check valves on the breather hoses, it doesn't seem to make sense to extend them to avoid getting water in the component during water crossings.

Micah

 

I haven't found them on the transmission or transfer case yet but I did extend them for the front and trear diff. They have white plastic devices on the end of the factory hose. Doesn't really look like a check valve just something to keep out the dirt. I extended the front up to the brake pod and the rear up into the space behind the left turn signal. When I drop my skid plates I plan to do the same with the trans and transfer case.