Can anyone tell me what this thing is? It's a white plastic valve that's plugged into a 1/2 in tube that comes up near the battery. It seems to be leaking radiator fluid. I haven't been able to find out what to call it to see if I can get a new one. It has a top that's very loose but can't be either tightened or removed. How would you know if it's broken? Thanks

 

Looks like a axle vent. and its probable leaking axle fluid.

 

Thanks a lot JKeaton, it the front axel vent. Now that I know I am able to search for solutions. It sounds like cutting a fuel filter into the line solves the weeping problem.

2000 Durango 4.7 SLT 4X4.

 

IF its leaking fluid, the axle is likely overfilled. Did you drive through water recently? Or have the axle serviced?

 

Yes, at the Pennzoil Speed Oil Change Center.

 

Sounds like they overfilled it. I'd take it back and show them. i don't trust those places to put air in my tires correctly.