Dan...I fully understand and accept the fact I lost 6 months of warranty on my frame. My question was where is the proof this causes damage?
There's no proof I've ever seen. If you're hanging 2 bikes in back of the trailer, you'll probably be fine. But my non-engineering opinion is that the more weight and bounce and stress you put on the back of the frame, the more exposed you are to creating a problem (yes, you can call me Captain Obvious).
Some people have in the past expressed the idea that they're protected because the frame manufacturer would have to prove the hitch caused the frame problem before they could deny a warranty claim. But the idea that there is a burden of proof on the manufacturer in order to deny warranty may be wishful thinking. From the searches I've done on Magnuson-Moss, I find nothing to that effect. Rather, it appears there is a pretty significant burden of proof on the consumer if you want to challenge a manufacturer's denial of warranty.
And after warranty, if you're looking for a manufacturer to "stand behind their product" you surely wouldn't want them noticing your modification, because it gives them a good excuse to remind you you're out of warranty.
Cookie, I'm guessing you didn't volunteer info about your hitch.
I'm not trying to scare anyone away from installing a 2" receiver hitch. But if you're planning on putting a generator, or motorcycle, or boat or car behind your trailer, well that might be a different story.