Speedometer gear in case

[Scott_Meier]

My cruise control pulses going down the road and the speedometer has a slight bounce.... i have put a new cable on it and a new speed sensor and have tried a different cluster n it still pulses.... the gear on the speed sensor doesn't look bad ... the transfer case is got from a salvage yard cuz the electric crap in my truck had issues and after trying a shift motor control module n buttons it still didn't fix it so I found a manual shift transfer case in a salvage yard......its a 1993 could there be something wrong with the gear in the transfer case looking threw the speed sensor hole the gear looks fine but I can stick my finger in it and turn the gear .... is that normal..... I miss using my cruise control and the cruise control module diaphragm dosen't seem to be leaking so could there be a issue in the transfer case?