For those of you who are worried about putting an oversized tire on the stock rack, here are some tips. One of the main reasons got people to have taingate damage from a ovesized spare is because they allow it move. The stock spare, when on the rack sits on small rubber bumpstops. These help steady the tire so it doesn't shake. Two things happen when the tire and or wheel are replaced. If the tire replaced on the stock wheel, it may no longer fit. This requires a extension bracket. The second scenario is if the wheel is replaced. In most cases, the backspacing is not the same as stock so the tire no longer rests against the stops.
Because the tire is not longer resting against the stops it can now shake on the rack. Constant rocking will cause the sheet metal to tear around the mounting locations which is not good. To prevent this, the bumpstops must be extended to sit against the tire. To do this is to shim the bumpstops far enough to rest against the tire.
To go it cheaply, you will need to figure out how much further the bumpstop needs to be extended. To do this measure the distance between the existing bumpstop and the tire. Add a bit to that so the tire sits firmly against the stop. Then head to your local hardware store and get bolts that are that much longer then stock. While you're there bit a foot or so length of ABS pipe. This stuff is thicker then PVC and not white.
Cut the pipe to length and place it between the tailgate and the bumpstop. The bumpstop does not need to be that tight since it will begin to cave into the pipe. You could add a washer to prevent this but really it isn't that necessary. Once your done, put the spare tire back on and it should not longer rattle. This many not be the perfect option, but it should be a problem for most tires. I have a 34x9.5R15 TSL on a 15x8" steel wheel for over 2 years and no problems. I do check it once in a while though.
