OK so i have a 98 dodge ram 1500 5.9L 4wd and so about a month ago my 4wd just quit working but the 4wd light was on and never blinked. I presumed it was the actuator since the vacuum lines were good. Once i replaced it, it seemed to move with more force than the old one so i figured that was it. It wasn't. i hooked everything back up and i still cannot get the dam thing to work. The collar slides fine and when i put the new actuator on and it didnt work, i left it in 4wd and took the actuator back off to make sure i didnt put the fork in and missed the collar, But the collar was slide the to left locking in the hubs so the actuator worked (so i dont think vacuum is the problem in this case)but still no 4wd. The front drive shaft turns when i drive so im guessing its something in the pumpkin because right now thats the only thing left that i have not checked and i want to get someones oppinon before i go taking the cover off and wasting money on some differential fluid. Also only in the morning when its cold will my check engine light blink and then go on the whole time but My check engine light it always ON because of my o2 sensors. The service4wd light has never came on. Any suggestions before i waste anymore money? Also the way im testing if the 4wd is on is theres snow on the ground so i do a burnout in the snow and i stick my head out the window and see if the front wheels spin. Also when my 4wd first went out i was in my driveway that hasnt been plowed and i floored it and it almost sounded like metal on metal but not a loud noise but still a noise came from something. Differential fluid is topped out so its not likes its out of fluid and was running dry.