I can't answer with any science or mechanical proof, but I don't think it will be much of an issue. I run 28x14 Bighorn 2.0's on my machine and my current spare is a 26x12 Bighorn 1.0. I had a set of tires from my Honda atv so I just bought a cheap steel rim for it to fit the T4. I consider it a temporary spare, as in, it will get me back to the truck. I don't know that I would run all weekend with it on there, but I'm sure it will get me out of a jam if I ever do need it. I keep about 12 psi in the spare so it runs a little big, and I run my 28's at around 6 or 7 psi so they are actually pretty close in height when under load on the machine anyway. So I guess I would say if you want something that you can throw on and leave it for good, I would look for a 27, but if it is just to get you home until you can replace the other one, go for it.