Possible tranny or rear end?help

[Dirtracer27x]

So I was towing my Polaris in Tahoe and on the way home the truck just dumped like it fell into neutral.i was getting a flashing 4wd in progress light for years but never tried to engage. Had the tranny built 15k miles ago with billet valve body torque converter etc. truck is a 2016 tradesman 6.4 hemi with 4d manual shifter on the floor. I messed with the floor shifter and got the truck to move back on the road.after a few miles it gave up and now the rear wheels are locked up when they put on the tow truck. Motor runs fine when I go into gear I hear some grinding from what I think might be transfer case or tranny. Could the tranny or transfer Cause the rear wheels to lock up? Took to the tranny shop because I have a 36k warranty on the work, he said the tranny would never lock up the rear due to the design.any help or guidance would be helpful,on a tight budget and need the truck fixed.

 

[Daw14]

Sounds like the rear locked up. Is there any signs of leaks at the pinion ?

 

[18CrewDually]

Pull the rear driveshaft (with wheels chocked), put the transmission in N and t-case in 2wd to see what is bound up.

 

[Dirtracer27x]

Looks like the transfer case blew, rear end is good so far a as well as tranny. What would cause the transfer case to just take a crap?

 

[Wild one]

Looks like the transfer case blew, rear end is good so far a as well as tranny. What would cause the transfer case to just take a crap?

In the majority of cases it's lack of service or abuse that takes out a transfer case

 

[Dean2]

By your own account, the transfer case has been warning you for years with the flashing 4WD light and you ignored it. My guess is, whatever was causing the flickering light finally pooped the bed good.

 

[18CrewDually]

Looks like the transfer case blew, rear end is good so far a as well as tranny. What would cause the transfer case to just take a crap?

In some cases I've seen the pickup hoses break or the oil pump itself fails. Lack of ATF from small leaks or never servicing it will kill them too when they run out of clean free flowing oil.
The pump rides on the output shaft and the pickup filter and hose goes towards the bottom of the case. Alot of people have no idea there's an oil pump in there but is also why it uses ATF instead of a thick gear oil. Without the pump fluid cannot get to all the bearings so they run dry until they don't.