Having ANOTHER issue with my week old Savage X.

I'm almost 8 tanks of fuel into the truck (first four were break in, so only four actual tanks since break in. I still haven't even gotten the thing leaned out yet!!).

I was running it this afternoon (about 73 degrees outside temp.), got through almost a tank of fuel, and it rolled to a stop, engine still running, but not engaging the tires. When I give it fuel, the engine revs and smokes (the carb is opening OK), but it wont move. I let it cool for about an hour, restarted it, and it ran fine for a minute or so, then back to the same ordeal. Engine revs, but no movement.

Called the guy at my LHS, and he said it sounded like the spur gear was eaten up. Checked the spur gear and it looks fine with no wear or apparent problems. What next??

This is my first Nitro RC of any kind, and I have no clue about how they work. I'm not overly mechanically inclined, and don't want to start tearing it apart without knowing what I should be looking for. May have gotten in over my head with this being my first one, but ya gotta start somewhere!!

Do these @#$% cars ever just run without having to do a bunch of work on them??!! Every day that I've had the thing it seems that I've had to do something new to it!!

All help appreciated!!