My sander keeps stalling - any ideas?

Hey all, I've got a DeWalt 5" random orbit sander that's been acting up. It starts fine but after a few minutes of use, it stalls under load, like when I press down a bit harder. I've cleaned the vents, replaced the pad, and checked the brushes - they look ok. Any thoughts on what could be wrong?

Sounds like it might be the thermal overload protection kicking in. If the motor is getting too hot, it'll shut down to protect itself. Have you checked if it's really hot when it stalls? Also, are you using it with a dust collection? That can clog the airflow and cause overheating. Maybe try a different dust bag or hook up a vac.

I had a similar issue with an old Bosch. Turned out the switch was going bad and intermittently losing power. But it would stall when I pushed, not just after a few minutes. Another thing: check the power cord for damage, and if you're using an extension cord, make sure it's heavy enough. Low voltage can cause stalling too.

Cheap fix first: make sure the backing pad is spinning freely. Sometimes the bearing seizes and the motor can't turn the pad under pressure. Also, if you're using a really aggressive grit, it might be too much for the sander. I'd try a lighter touch and see if it helps, before you start tearing it apart.

Thanks for the suggestions. I did check the pad spins free when it's not under load, and I've got a decent 14-gauge extension cord. I'll try the dust collection thing and maybe run it without the bag to see if that helps. If not, I'll open up the housing and look at the switch. Appreciate the help!