Rattling noise in 2wd

[Jakers_AK]

So for a while now I've been hearing a rattling noise when driving down the road (not the timing chain rattle I know what that sounds like). It almost sounds like a chain or a gear in the t case maybe. I just tuned it out for the longest time until the other day I realized the noise goes away when i put it in 4x4. And idk if it's related or not but my obd scanner won't communicate with the 4x4 module. Any ideas?

 

[410Fortune]

Not sure I’ve ever talked to the 4wd control
Module in one of these trucks, they do have a iso wire that is for communications but kone of my scanners will
Locate or report any info from 4wd

I would check your front driveshaft make sure the front u joint is ok and the ball flange where it connects to the t case

You should put the front end up in the air tires off the ground get underneath and have a look

The t case in these trucks is very strong, not very often would they make a chain noise internal unless you ran it dry?

Time for a shake down test, with the truck in n and in 2wd support front end safely chock a rear tire and get under there with a flashlight and pry bar… see if you can find something loose and that would rattle

E brake cables
Front driveline
Exhaust shields

Cv axles
U joints
Front diff
T case
Trans mount
All suspect since it apparently goes away in 4wd my first through it is u joint

 

[Jakers_AK]

Not sure I’ve ever talked to the 4wd control
Module in one of these trucks, they do have a iso wire that is for communications but kone of my scanners will
Locate or report any info from 4wd

I would check your front driveshaft make sure the front u joint is ok and the ball flange where it connects to the t case

You should put the front end up in the air tires off the ground get underneath and have a look

The t case in these trucks is very strong, not very often would they make a chain noise internal unless you ran it dry?

Time for a shake down test, with the truck in n and in 2wd support front end safely chock a rear tire and get under there with a flashlight and pry bar… see if you can find something loose and that would rattle

E brake cables
Front driveline
Exhaust shields

Cv axles
U joints
Front diff
T case
Trans mount
All suspect since it apparently goes away in 4wd my first through it is u joint

I'm going to see if I can get it up on my friends lift so I can have someone in the cab operate the switch and see if i can pin point the source of the noise underneath. I should clarify the noise. It's hard to put in to words but it's not just a random clanky noise. It is a steady rattle like if you were to stick a wrench in the spokes of a bike tire as it was spinning. If that makes sense lol