Easiest way to test 4X4 operation

[ProTech LEW]

2009 RAM 2500, 6.7L Cummins Automatic, Manually shifted 4X4.

Seems to not be engaging the transfer case. Previous owner had installed Warn Locking Hubs also.

I'm not sure if it's a problem with the transfer case, front diff or locking hubs.

What would be the easiest way to test each part of the system?

On jack stands? Remove front driveshaft and manually put the system through it's paces?

 

[Fast69Mopar]

2009 RAM 2500, 6.7L Cummins Automatic, Manually shifted 4X4.

Seems to not be engaging the transfer case. Previous owner had installed Warn Locking Hubs also.

I'm not sure if it's a problem with the transfer case, front diff or locking hubs.

What would be the easiest way to test each part of the system?

On jack stands? Remove front driveshaft and manually put the system through it's paces?

Putting the truck on stable jack stands is how I do it if I don't have a scan tool with me or it's a fully manual transfer case.

With this being a 12 year old truck with 12 year old transfer case shift linkage and bushings, take a look at the shift linkage and make sure the bushings are still intact.

Disconnect the linkage from the transfer case and see if you can move the shift lever manually with a large pair of Channel Lock's. If you rotate the shift lever forward to the furthest position that will be 4-Hight. If you rotate the shift lever towards the rear you will go back to 2WD, then to Neutral and then to 4-Low.

 

[kurek]

Lift the front axle off the ground. Engine off, transfer case lever in 2 wheel drive. Lock both hubs. Rotate one of your front tires by hand. You should see either the other front tire rotate backward (if the front diff is open) or feel some resistance and see the front driveshaft rotate (if a limited slip is in the front axle). If neither of those things happens you may have a problem in one of the hubs (seized, stuck) or something broken in your axle.

 

[ProTech LEW]

Thanks for the reply. Will do.

 

[ProTech LEW]

It seems to shift fine. Just isn't pulling with the front wheels. Thanks FAST69MOPAR that will also help when I get under her this afternoon.

 

[ProTech LEW]

It finally dried out here enough to work on my truck. I did as kurek suggested and tested the front diff and lockers. Neither one would lock. Took them apart and found that they had been greased. Had read yesterday that they may not work if greased. Cleaned them out and one started working. The other one is still a slacker. I thought that the control knob and spring may have been weak on that side so I swapped the two. No change, same one still wouldn't work. As I was giving up for the day and reassembling them I saw a difference in them and have attached short videos that show the difference. What would make the outer gear ring on the non working one be loose?