So I got a new leftover in Jan this year. It had about 350 miles on it and about a month ago while chuggin through a good mudhole.. snap, crackle, pop.. and stopped me in my tracks. I rocked it around a little and got out of the hole ( 2wd only ) and didn't see anything wrong. started to ride back to the trailer and sounded like marbles in the front diff. Cleaned it up, took to the dealer and they replaced the complete front diff. They said it was a mess in there and they never seen anything like it. Also have been fighting with them since purchasing about the weak (2 yr old battery) and they would not do anything with it. I had to break down and buy a new one for $90 bucks. Also having the overheating problem (at least I think a prob) b/c the fan seams to always be running. After the first time around I discoverd the radiator is a dirt magnet and try to keep it clean, but still the fan seams to run allot when other machines I ride with are not running. Anyway I love the beast. Stock tires are starting to wear and can't wait to get a new set as the stockers are horrible in the mud. I wish there were more dealer around though as I think the local shop in Chambersburg, PA is sticking me on the cost of maintenance, but while under warrenty I dont want to take teh chance of doing things myself yet. Sorry for the long post...

 

I've also got an '08 TRV 650H1 - she's a beast.....and I luv 'er!!!

It's proven to be extremely reliable in 1350miles...but I too have had a few minor issues:
- main seal behind the stator leaking/replaced under warranty
- wacky fuel gauge - replaced sender under warranty
- loose handle bar pillar/column - fixed w/longer bolts

That's bout it.

I've got some thoughts about your problems:

FAN RUNNING:

I installed a mechanical temperature gauge on mine because I too was concerned about the fan running too much..........nope it's normal. The TRV runs up to's 185F - the fan kicks in - and pulls the temp back down to 130F. On hot days I've seen the gauge push 200F.....but she always cools down. I also added an overflow bottle from an '07 650 and it's never overflowed. I also replaced the 15amp fan fuse w/a 15amp mini circuit breaker.

BATTERY:

stock batteries are CRAP. Especially ones that have been sitting unused in late model machines. It's quite common for them to die shortly after they start getting regular use. I personally run a dual-battery configuration w/the 2nd garden tractor battery tucked up nicely behind the fuel tank. It gives me more overall capacity fo when I'm running all my snow-plowing accessories

TIRES:

I dumped the stock tires and went with MUDCATS made by TBC - wow! Night & day riding improvement and overall handling.


FRONT DIFF:

the '06- early '08's are NOTORIUS for a very poor spider gear spot weld in the front diffs. LOTS of self-destruction when under torque. Many have welded them themselves - I haven't. AC is replacing them even out of warranty.

My rule is.....breakage happens.....it's an OFF ROAD MACHINE....do what ya can in the preventative department...and go from there. I also don't intentionally swamp my TRV or drive the living crap out of it. (ok...the OCCASIONAL mud hole)
The amt of $$$$ I've got tied up in AC machines....I've gotta milk every last mile out of them with care. I'm religious/**** when it comes to washing/cleaning and maintenance. I'm forever going over each machine looking for potential problem areas. FORUMS like this one are a HUGE help in that dept!

The TRV runs completely on AMSOIL synthetics as well. Both the engine and diffs.

BOTTOM LINE:

I luv my TRV...tooo many advantages over other quads IMHP. And when the times comes to replace 'er......I'll get ANOTHER one (w/pwr steering)

 

Thanks for the reply... I have the cat care warrenty for another 2 1/2 years so I hope all the bugs get worked out. But your right.. If I treated my Cherokee like I treat my Cat it would break something to. Looking into those tires now... But an almost sold on the Bighorn 2's..