i have a 96 1500 5.9 when its in rwd the truck runs mint, but when i engage it into 4hi its kind of loud and i feel vibration, the 4hi works fine, it just doesnt feel and sound smooth. also when i engage it into 4hi it takes liek 10sec for the light to come on or when i put it back in 2hi it also takes 10sec for the light to coem off.

 

getting a vibration at what speed and on what surface? rams have a part time transfercase and are not ment to be driven on dry roads or at speeds above 50 MPH

 

on wet surface, like when its raining,its loud from 1-50mph

 

Have you looked at the front drive shaft u-joints?

 

That double cardan assembly has a center ball bearing in it. If it goes bad, it makes a loud, dull, rubbing sound.


Good luck.

 

also check your front axle u-joints they go on mine quite frequentley and cause vibration in the front end