Suburban Oven Not Lighting

I'd like to know how common it is to have to replace a thermocouple in an RV oven.

My pilot will light, but as soon as I release the knob and try to turn the oven on, the pilot goes out. It doesn't matter how long I hold the knob in and heat the thermocouple. I believe the thermocouple needs to be replaced, but it seems like a fairly unusual thing to me.

(All other gas appliances work perfectly, including all three burners on the cooktop.)

Have any of you had to replace this?

Is there a different cause I should be considering?

Thanks,

-Speak