ford ranger 2004 5 speed standard 4x4 . I have been putting off the mild clunking noise and I don't do allot of highway driving but Idid notice the other day when I was on the Hwy at around 110Km\h to about 125Km\h I get a vibration .
I crawled under my truck and noticed that the the rear Drive shaft coming from the transmission under the rubber boot has a little play I can move it up and down and hear a knocking noise. could this be the culprit of both the shift clunk vibration ?

 

Most likely u-joints.

Is the rear rubber seal leaking, it will if output shaft is vibrating around in transfer case
If no leak then replace u-joints on spec
Also with rear drive line unhooked, start engine and run thru the gears to see if you still get that clunk, 2WD of course, lol

 

no leak that I can see I seen a you tube video person has the same drive shaft with same play and knocking noise the exact same on mine but I have no oil area the area its all dry

 

Thats the slip yoke, my mistake, I though you were referring to the output shaft on transfer case

Fix for that is here: https://www.ranger-forums.com/drivet...-sticky-73528/

 

Great thank you ,