Rear End ????

I need some input. When my truck is loaded with hay be it either a 16' trailer with 100 bales or the gooseneck with 10 rnd bales. When I leave my drive and turn sharp onto the pavement the truck seems to jerk. So I am thinking maybe the rear end is not unlocking to allow the outside tire to turn faster. Some more possible evidence. I bought new tires 20K miles ago and the rear tires are worn pretty bad already. The tires were Nito grapplers. Not really concerned with the tires, I dont want to be back into hay season and have the rear end break. If I jack up the rear of the truck off the ground is there any way to test if the rear end is working right.

 

raise one wheel off the ground, engine off, trans in neutral and parking brake off. remove wheel and bolt special tool 6790 or equivalent to studs
use torque wrench on special tool to rotate wheel and read rotating torque,if rotating torque is less than 30 ft lbs or more than 200 ft lbs you need to service the unit.... i just replaced the clutches in mine, it was a piece of cake. but since your's is grabbing, maybe all you need is some friction modifier additive

 

where can i get one of those special tools

 

Does it feel like you still have it in 4WD? Jerking about every second while in the turn? If so check the condition of the front axle hub u joints for looseness.

 

I have felt that before when it was left in four wheel drive. This seems to feel like it is from the rear.