97 sierra manual 4x4 problem

[97gmc]

I have a 97 with manual 4x4 and it won't engage front end when I put it in 4x4. I put it in 4 low and the transfer case goes on low but front end doesn't engage. Same with 4 high. I pulled out the actuator to see if it was functioning and when I pull the lever the piece pushes out. Have tried a different actuator with same results the are both used as well. Any help would be great. 

Thanks

[97gmc]

Figured it out. It was the mode fork in transfer case. But with new actuator front end doesn't engage. I pulled old actuator out stuck in a screwdriver and it engages front axle. Put new actuator in and it doesnt engage. When I have actuator out and put in 4 hi the actuator goes out. Just wondering maybe not enough voltage or amps to give actuator full power? 

Any help would be great

[97gmc]

I did more research and I see it had the actuator upgraded to the electric not thermal actuator. In thinking the space is missing. Where does a guy find one of them? 

[Logan Lanfear]

Usually the 4x4 on these trucks works pretty well besides that actuator occasionally going out.  So you've verified that the actuator works.  I couldn't tell you how far it actually goes out, that measurement would be hard to find anywhere.  Are you sure it was seated all the way when you installed it into the truck?  Either that or it sounds like you have problems internally.