Transmission pan bolt broke off inside

2010 CHEVROLET COBALT
100,000 MILES
Avatar
SETH7383873
  • MEMBER
  • 15 POSTS
I went to do a transmission filter change and while taking the bolts out one of them stripped and snapped off inside. I’ve tried drilling a whole into to try and get a bolt extractor to go in but it will not budge. I’ve also used penetration oil on it but cannot get it out.What else could I do to seal the transmission pan without that bolt?
Apr 23, 2020 at 4:26 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,193 POSTS
  • ASE Certified Mechanic
You could use a form a gasket to help seal that area, but it may not last. Have you considered drilling the entire broken bolt out and then re-threading the housing and using a different bolt? That is what I would honestly be doing. If drill enough of the bolt out, it should come out. If that doesn't happen (as you mentioned) get a drill bit the same size and the bolt and drill it entirely out and tap new threads into the housing and then replace the bolt with the new size.

Let me know if I can help.

Joe
Apr 23, 2020 at 4:41 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.