No need to turn this into a gas verse diesel argument in this thread, that will go on forever...lol. Anyway will the gas engine pull your 10k load? Yes. If you take it out of florida like I do, don't sweat it. The trucks not going to blow up, or crawl up the hill. It will find a sweet rpm spot and do the job as it's intended to do. I run 5th in florida, I lock out 6 gear. In Georgia I will run 4 th in the hills around 3000-3200 and keep 65. If I need more power I have it, rpm hitting 3500-4k does not bother me. Today's gas jobs run circles around yesterday's, just like some diesels as well. I don't pull more then a few trips a year, so owning diesel anymore is not desired. I am a fan of the the Dmax, however I love my 6.0 gas job, and there are so many advantages for me to own one. My thought is drive the big three offerings, and pick out which gas engine you like. All 3 have really proven themselves over time and will give you many years of great service.