[racergt]

I picked up my youngest son a used Evader St a few weeks ago. When I move the right rear wheel forward the left rear wheel moves forward as well. Now my oldest son has an Evader BX I just picked up for him and when I do the same thing to his right wheel the left wheel moves in the opposite direction. Which of these are correct?

 

[EvaderMaster]

In general, when the car is in the air, moving one rear wheel should make the other rear wheel turn in the opposite direction. The BX is correct.

Check the differential. It may be adjusted too tight or melted/fused together from too loose of a setting and the subsequent overheating that occurs when it slips too much.