One other suspect is the transfer case switch. CAD, ya gotta love it

 

Isn't there a fork in the transfer case as well? Maybe that is what the previous post is about. When you pull the lever to shift into 4WD the lever is actuating a fork in the tcase to engage the front drive shaft. You might make sure the front drive shaft is actually being powered. My 2 cents.

 

well it looks like V10 has the answer. Will order one tomorrow and post if it did the trick. I called today and priced the vacuum switch that is mounted on the front axle, little over $200, think I will start with the t-case switch which does not appear to be working properly. But if i do need that other one I will be going with the posi-lock thing that ljpierce has on his.

 

got the t-case switch today ($19) and they had it in stock so that should tell us something! Took 5 minutes to replace it and I'm feelin good,,,,till I pulled out of the garage and found out it still would not engage.[:@] Came in and re-read this thread, decided that the only thing left was the vacuum diaphram on the axle. Went out and took it off and found that it took some real force to slide the fork into the 4wd position. After moving it back and forth a few times it got much easier, so I continued wiping it clean and moving it. Reinstalled it and jumped in started the truck and slid it into neutral and yanked it into 4HI, pulled it to drive and the darn light on the dash came on, YIPPEE!! Then I went down to the corner where there is a stone parking lot and gave it a try IT WORKED. I guess that what dodgeitri said about engaging 4wd at least once a month may be a good idea just to keep things moving freely. Thanks to all who made posts for helping me.[sm=icon_rock.gif]

 

According to the owner's manual, everyone with a 4wd truck is supposed to do so. I take mine offroad the first Sunday of every month for a drive through the woods.

 

glad to hear you got it fixed Sometimes its the simpler things that come back toy get ya.