i bought a 85 dodge 150 mud truck and has 93 axle the same just newer and its not engaging to 4wd it was working when i back up but drive i had nothing but a poping nosie.. now thats all i get and im new to this manual locking hub?? i dont know if its a bad hob or something in the pig or axle...i took both apart and both are greased good nothing looks broke i did find a couple small metal shavings..but then im not 100% on what im looking at.. any help would be great

 

Is there a bulge 1/2 way between the pumpkin and the driver's side wheel on the axle tube, with a couple of hoses and a wire connector going to an actuator? If so I'd wager that it's not functioning properly.