its a small approx 1/4" hose about 12" in length and seems to go nowhere.....its closer to the left wheel(if facing the rear of the truck) on the rear axel. it had a rusty clip on the end that was dangling...is this something to worry about?

It may be a air vent hose. Usually the other end is attached as high as possible under the bed or floorpan, ... whichever. Supposed to keep the dirtys out of the axle.

desimunda-12ounce is right--i have a 99 ranger and have seen it-so i went out just this minute and crawled under.it is clipped to the top lip of the frame above the electrical wires that go to the tail lights.there is no end on it and the open end points backward.your clip must have just let go

thank you gentlemen. i just tied it to another hose...this savesme a trip to the mechanic!

It's not a bad idea to plug in a small plastic throw-away (gasoline) air filter in the end of the hose. This will help keep more stuff out.

It is a vent for the axle to prevent it from pressurizing. Good idea to install filter and secure it as high and as far from dirt as possible. Recommend you have opening facing down.