Our NVG241OR Rock-Trac transfer case works quietly and is strong. The 4.0:1 low range is great for crawling. It isn't so great when trying to climb sand dunes. It looks like an Advance Adapters RubiCrawler is in our future, so we can also have a 2.72:1 midrange. Tom Wood's Custom Driveshafts built our front and rear 1350 CV driveshafts.