Spare Tire Project

Our Jayco 23ft Class C motorhome had the spare attached to a carrier which attached to the rear bumper. Was still very snug after 40K miles. We kept it covered with one of those plastic spare tire covers.

Our current Aspect 26A has the spare mounted on the back with a very nice metal cover so no uv rays get to it. Have about 20K miles on this one. I check the tire pressure periodically.

Be sure to mount it inside out.....turned around so the flat side is against the carrier. You may need an extension to reach the nut or just use the lug wrench to tighten it down.

I feel much more secure with a spare tire on the back. I also got a torque wench so I can properly torque the nuts. Then I practiced taking the rear tire off and putting it on just to be sure that I could.

Good to have a spare even if you have road side service. That way you don't have to pay big bucks for a replacement in the middle of no where.

I wouldn't do it. That's a lot of weight bouncing at the end of a rolling earthquake...

I'm spoiled by the undermounted spare on our Winnebago -- sits snugly between the frame rails on top of a couple pieces of steel tubing. Keeps it out of the way, and no worries about UV exposure...

Winnebago mounted my OEM spare tire on the back wall of my rear basement. The basement at that point is high enough for the tire to stand upright, bolted to the wall.

Not safe to carry spare loose in storage compartment. Ours is mounted to the front wall of storage compartment in our Tioga 26Q.

I saw one once that you pulled a latch and the rear bumper rolled out like a drawer and the spare laid in it. The slides appeared to be garage door track and rollers.

Dusty

Just me others might want to, but I wouldn't not after looking at what your talking about https://www.google.com/search?q=Stromberg+Carlson+TR-1+bumper+mounted+carrier&source=lnms&tbm=isch&sa=X&ei=q-xpUtfRG9HSiAKpyYH4DA&ved=0CAcQ_AUoAQ&biw=1366&bih=620 maybe a small trailer tire with a good strong hitch. I think your tire weighs maybe 80 pounds or more and it is going to be mounted at the very end of the "back of the bus" bounce wiggling around. If you tow, I would get it up front with a good strong front hitch (square tube) If you don't tow, mount it in rear hitch. IMO
You said "I'm a concerned it may not snug down properly because of the dually wheel." Yes, good catch with the offset wheel and bolt keeping it on. Mine only goes on one way (inset to rack)and four-way wrench bottoms out on tire before nut is tight. I just use an extension to get bolt tight. I will say that is not the worst place to carry a spare tire. Saw one going up freeway last week with spare tire chained to luggage rack on top of RV just bouncing along on the roof.
edited part: I like something like this although I would like it even more sturdy. http://www.etrailer.com/Trailer-Cargo-Control/Curt/c31006.html

Tried to send you a PM with no luck.

Search for the thread "Spare Tire for our class C". There is a picture on the second page of the mount I used. Bought it at La Mesa RV (it is in their catalog), for $28. Very secure and mostly out of the way. Our bumper is extremely robust, multiple large bolts holding thick steel plate in place. If you bumper doesn't sound like that you may want to get it reinforced before hanging a fairly heavy spare back there. Some bumpers don't even do well with a simple bike rack so it is worth checking. If you need more pics or info just let me know. :C