4wd works, but transfer case is making noise

During this crazy weather we are having, I got out to deliver firewood to a friend and used 4Hi for bit. It worked, but was immediately noisy - almost like a clicking that increased and decreased with load and speed. Checked underneath at a gas station to see if anything obvious underneath amiss, but saw nothing. No fluids leaking and no smell of anything wrong. Is this a low fluid issue? Bad transfer case? Anyone experienced this?

 

That could be the traction control doing what it does. Find some dry road and try driving in a straight line to see if the noise goes away.

 

Definitely a drive line issue. Took it to my mechanic to see if they could just check fluid and test drive. Transfer case slightly low, but no leaks. Topped it off and checked for any metal in fluid. Nothing loose and fluid clean. They think it is actually in the front diff. Once everything melts here we will do run out tests while on a lift to isolate the noise and confirm. May need to replace the diff. Thankfully used assemblies are not expensive. 4hi and 4low are working, just noisy.

also wondering if this would be a good time to consider a diff upgrade to something that locks - i guess that would no longer be the cheap route.

 

The driver's side needle bearing is notorious for going out, that that tends to make a noise when you aren't in 4WD. Still, the ECGS bushing install is no big deal if that's what it is. Diff replacement should be a last resort.

 

That was an option that was mentioned by the shop. We will just see what a more thorough diagnostic shows next week some time.

 

update: drove it to the store in the new snow and ice. Used 4Hi just when needed. on the way home sitting at a light in 2Hi and Trac control, ABS, and 4HI/4Low lights all came on dash. 4hi and low flashing. Not sure what it means or how this and the clicking are related.

 

Any update?

 

Truck decided it wanted to be RWD?