I hauled a 2.5 shortblock, 4wd AX-5/231, 2wd front beam, a bucket of misc. trans pieces, and a spare gas tank in my 2.5. Had an AX-4 at that point, 3.55 gearing. Get-up and go was just fine, stopping wasn't half bad, only noticeable difference in driving was the back liked to sway a lot. MJs don't have a rear sway bar, so watch the turns if you've got anything heavy in the bed.