I agree, I would just remove the tire and the carrier, then re-install the bolts back in the holes to fill them up so they don't leak

 

Put a real spare on there, you will wish you had one one day when you need it.

They also make locking lug nuts for those that have nice rims/tires that make it difficult for the average @-hole to steal your tire. You can find the Rover ones online and on eBay with regularity. Worth it to have a tire around for when you have a flat.

 

Your truck is an AWD, so if you get a flat, it's not like most cars where you can just throw a dorky little spare tire on there, you need the same size tire or you'll be messing up your drive train. That is why you need the full size spare.
I've run, 33' spare, high lift jack and a 5 gallon gas can on that back door with no issues.