Hey tinyrc!!! You're a genius! It works pretty well!!
as you said a length 3 axle (about 1 inch for those of you not familiar with lego measurements) and a thin lego nut works wonders!
You may need to finesse the axle onto the rod, but a pair of needle nose pliers help. (pic 2)
also, remember to take a small screwdriver and push any excess length of axle
away from the body of the car. you want as little axle to stick out past the nut as possible. (pic 4)
this fix is not perfect though. The wheel still falls off if you take a hard hit, but it no longer falls off on a simple turn. becareful if your wheel does fall off though I spent a couple minutes fooking for the little nut which managed to roll away after I crashed into a table leg...
For all you hardcore racers, you may want to stick a little CA glue on the end of the nut to keep it on... but be careful not to glue the axle into the steering hubs!
THUNDERER: For a toy (let alone a LEGO) it came at a reasonable $69.99 I figure it's cheaper than a TYCO and more than a RADIO SHACK...
I got it at
www.legoshop.com (the Lego online store)