I was doing some research on truck pulling for our club and came across this. http://duramaxracing.com/ I thought it was pretty cool considering it's pretty much a stock motor. The cool thing is he has fun with it, but also uses as a daily driver. I know the same can be done with Ford or Dodge, but considering this is a GM site. Plus it shows that a locker can be used in the front end of the newer truck. Granted it's in a straight line, but there is enough drag on the truck that all 4 wheels spin (full weight of truck, engine, and tranny) over front wheels with pulling tires and all the torque (well as much can reach the front wheels) and the shafts show no signs of breaking or giving up. Yes I would like to see how they would do when turned, but considering this abuse, I'm sure they could take more than a D44 offroad (just my speculation, I have no hard facts to back that up other than having seen lighter trucks blow fresh u-joints in the front axle when locked up and pulling). Anywho, just a gratuitous GM diesel post. Some year I will have my own.