Further reports from my KJ...
Well, I just got done hauling around a 6,840 lb genset for the weekend, at varying speeds and highway conditions. Also got to pull a fully-loaded 10,000 GVWR box van out of the mud, and I think the KJ performed quite admirably. As further proof that Chrysler doesn't know what the hell they are talking about most times, I offer the GVWR door sticker for your perusal: GVWR: ~5680 lbs
I had the genset weighed just for grins (since I was at a truck stop fueling up anyway) and found out the KJ's own actual weight is ~4500 with the crap I had in it. So... That little 4 cylinder engine is yanking over 11k lbs down the road without any problems, and STILL booking 18mpg while doing it! Gotta LOVE a diesel. Why do I mention the GVWR sticker however? The entire point of a tow rating is just what the vehicle is rated to pull... WITHIN the max of the entire GVWR... The engine has to pull everything, so thats why you aren't supposed to exceed the GVWR. But they only calculated the internal safe loading, and forgot the towing capacity in those numbers. Thats how you might do it on a passenger car, not on something with an actual tow rating. Idiots.
The point for posting in this thread however: At no point during this heavy-hauling did the transmission drop out of gear, even tho the SG was showing I was up to 12gph at one point... I'm guessing I don't have any fueling issues!

The SG also kept operating most of the time, it only locked twice in about 8 different trips with this thing, and all the destinations were over 40 miles one-way.
I don't know, I think that the Linear guys need to weigh in on this.