I read that too and had to chuckle. No, the engine is
not going to die in an RTV if you run out of power going up a hill. I've had an RTV900 and an RTV1100. Waaaaay back in early 2004, when the RTV900 first came out, I was one of the first people to post how it was impossible to get the RTV out of gear when it ran out of power going up a hill. This was the beginning of Kubota coming out with the pressure relief valve now standard on RTVs. In testing this, I drove dozens of different RTVs from the dealer up hills until they ran out of power and they all were very hard to get out of gear. However,
none of them died when they ran out of power! I believe someone is making something up based on how their HST tractor operates and trying to tag that story to the RTV.
Now, with the RTV1100, even with much more aggressive tires than stock on it, it never has run out of power in 4X4 low range on a hill. I've come up to some hills it won't climb, but it always ends up just spinning the tires whereas the RTV900 (with the same tires) would end up just grunting and not spinning any tires. In
no case has any of the RTVs died when pushing them to the limit going up hills. Even though it is heavier, I am well pleased with the power the RTV1100 puts to the ground for pulling and climbing. Heck, I've found the best way to break in the RTVs is to run 'em like you are mad at them. The change of the transmission filter at 25 hours as well at 50 hours made huge differences as did going with the Super UDT at the 50 hour service. Still, my RTVs seemed to get stronger the more hours I put on them.
I know a buddy of mine was kind enough to post this pic here in the past, but attached is a picture of my RTV900 with well over 2000 pounds of heavy wet clay in the bed. I dumped as much of a load as would pile up in the bed of the RTV and then hammered it to the floor during each round trip. After dumping literally hundreds of loads like pictured, I guarantee you my RTV ran far stronger than when I started that particular job. Better yet, it never stuck in gear again after flogging it for days with thousands of pounds of dirt in the bed. As you can see from the picture, I'm just a little fella. Don't tell my dad what I did to his RTV

All that dirt on the ground behind of it is just what fell out of the bed and wouldn't stay stacked up.
True, there are some minor issues with my RTV1100 and, very true, I'm extremely disappointed with Kubota's customer support. However, I think someone is flat out making up some things that are not true. Even if they are not, it would be an odd issue with that particular RTV that would cause it to die going up a hill. Still, with my experience with several RTVs, I opt to believe that story is not exactly true.
