Kubota "might" cover it....and this post will get long, and is worth a read for "any" sort of potential warranty repair.
Rust is one of those issues that could be caused from several things, ranging from-but not limited to-rust under the powder coat, which causes it to de-bond from the base metal, could also be scratches from shipping, dealer storage, dealer transportation, and anytime there's bare steel involved, it'll likely rust. Different parts of the country will show corrosion/rust faster than other parts, and different alloys will rust faster than others. Bare cast iron, freshly machined, will rust almost immediately...within seconds it starts to turn from gray to orange once it's truly "bare". 4340 steel will also rust but it takes a lot longer than, say, 1010 steel does. You get the idea.
Now then...the process of getting warranty coverage. You're going to have to visit your selling dealer and discuss it with them first and foremost. If they say no way, tell them to take pictures, then submit them to Kubota warranty department for pre-approval. If they refuse to do that, you can (1) go to another dealer and make the same request or (2) call Kubota's customer service line, with the details of your dealer visit(s) and their reactions.
Now the question that was asked in the original post was a little vague, especially without a photo. On a grill guard, it shouldn't have much bare metal on it. If it does, either the coating (paint) was applied too thin, or the rust started under the coating, or...the grill guard was used as a tie down point, scratching the coating off causing rust to form. If the latter, that is a dealer's (or owner's) responsibility-depending on who put the chain/straps across it without any sort of protection between the chains and the tractor parts. I have seen them come in on transporters directly from Kubota's warehouses, and the driver states that the chains were put on like that when he got to the truck. Fine, but he IS responsible for his load, and if it's damaged in any way, he's at fault until he can pass the buck back to whoever did it originally. And if that's the case, the dealer who accepted the load should have documented any damage so that dealer could not be held liable for the cost of repair. As it is, Kubota doesn't generally "like" to pay for shipping damages or missing parts, for whatever reasons. Sometimes they'll put it back on the dealer, and if they do, the dealer can handle it a lot of different ways...from telling to go pound sand, or they'll replace the part at their cost....or they'll send you on your way with a can of spray paint. All depends on the dealer and how they want to handle it.
BUT...if you can prove that the rust is UNDER the powder coat, and the coating is peeling off because of it, then Kubota "should" pick up the tab on it. Still has to go through the pre-approval process which takes time, and requires pictures. So be aware of that. That's how warranty works. A defect has to be proven to the manufacturer--and this goes for any warranty claim, period, non dependent on what type or brand. If a defect can't be proven, then they won't help.
good service I really think we are lucky to have this dealer close by.
