I've got a GE Gas Dryer. Dryer will start, then after about 2 minutes stop running entirely. Same thing happens when fluff only (no heat) option is used. Sounds like a motor problem, but I want to rule out thermostat. Any ideas on problem isolation and resolution?

I'd start with the belt. Inspect it for cracks and make sure it is taught. If it stretches as it warms up after a couple minutes, it may be too loose or slipping. This would cause the centrifugal switch to think the drum isn't turning and then it cuts the motor.

The centrigual switch may also be the problem. It could be faulty, causing the motor to cut out. Not all models have a replaceable centrifugal switch, in some cases you have to replace the entire motor.

The thermostats shouldn't be the issue sinnce the same thing occurs when there is no heat (assuming there really isn't any heat). Of course anything is possible, but it would be reasonable to rule out the thermostats at this point.

I am assuming the timer control is not the problem, you have tried different timer settings, right?

Finally, the motor could be faulty.