98 Suburban 4wd front end noise

[snetdude]

Hi, Lookin for some ideas of where to start. My issue is relatively new. After I push the button to engage 4wd the light goes from solid 2hi to flashing 4hi then solid 4hi fine. Once its in 4hi and while driving straight things sound ok the issue is turning. I have heard the noise turning right or left. It sounds like as if the 4wd is not engaged all the way and you get this loud clicking/clunking sound pretty sure coming from front axel. My wife has described it as a tink, tink, tink sound. Any help would be great. Thanks

[maxwedge]

Welcome to AF, very tough to accurately diagnose this on the net, you need to have the front axle engagement checked, this could be a transfer case issue or more likely the actuator for the frt axle is not working properly.

[snetdude]

Hey Max, If I jack the front off the ground the front wheels spin freely by hand while still off the ground i push the 4hi button i can hear the actuator and somthing at the transfer case make noise then the front wheels are locked and wont spin. I did notice the universal joint on the front drive shaft at the transfer case is very loose I can actually see the cross move in the cups so I may have lucked out depending on the weather I am going to change them both this weekend.

[maxwedge]

Yep, fix this first, may correct your issue.

[snetdude]

U-joint at transfer case was definitely the cause. Cups were bone dry rust metal on metal. Instead of smooth the cross was knurled ridges. The only bad issue was my brother helping me after I pressed u-joint through one side he took the torch to cut the other cup and when he squeezed the trigger to blow the molten metal away it shot through the yolk and ruined it. So at this point new shaft is on the way. DOH!

[snetdude]

Replacing front drive shaft solved my issue