Originally Posted by GerryH

I'd also suggest disconnecting the link to the servo and testing the steering by hand to see if there's any binding or other resistance. Try it with the front wheels off the ground. They should turn fairly easily by manually using the servo linkage.

What's strange is the 3-5 minutes. How's your battery? If you run for 3-5 minutes, shut everything down wait a while and start again. Does the issue start immediately? Trying to eliminate the battery and it's voltage as a culprit.