I had a FSJ (Grand Waggonner) once that spent time as a snow plough vehicle and after I bought it, I noticed it had a pesky "klunk" (I just don't remember if it was on take-off or stopping)......drove my three mechanic pals (and me) nutz trying to figure out what it was, until one of the fellows said "I think your crank is going forward and backward".....I looked at him, well, kinda like this   but sure enough, I dropped the oil pan and the middle bearing (I guess its called the "thrust" one) had the, I guess you call it the thrust portion of the bearing, totally gone and the crank WAS going back and forth. I was told thats common for snow plow vehicles........other than that all of my FSJs have been decent workhorses (they do like rust though, but they do put up with alot of stuff you don't do to a "daily driver")
 
(plus I seem to have a bunch of j20 stuff living here...and no, I've never owned a J20, just J10's and GW's)