Y GE gas dryer cuts out in the middle of cycles when hooked up the external vents, it takes afew minutes break and then restarts, when I unhook itfrom the exteriorvent it does a lot better, the vent has been cleaned so I donth think there is a blockage issue, the dryer is about 8 years old, that doesn't mean much as I just replaced the GE washer which was the same age>

I wouldn't be satisfied until I KNEW the vent was clear. Can you check at the outlet end to see if there is good air flow when dryer is working? Animal nest? Snow blocking? I'm sure there are other possibilities but I think any problem with the vent should be ruled out first. I guess my question is--When was it cleaned?