Broken transmission pan bolt

[Brian1133]

I dropped my trans pan and filter with a new gasket in my 2014 Tahoe Saturday. Luckily my flange exhaust bolts weren't rusted at all and I did it by the book by dropping the exhaust.
So I couldn't find my torque wrench and I tried to wing it, and broke a bolt. Trust me, it didn't take much.
I'm not leaking fluid but I'm wondering if anyone has had experience drilling out a pan bolt? Should I get all new bolts cause I might have stretched the other bolts too much?
I'm concerned now that if I try to remove the other bolts the heads my break off, too.
Should have just gone and rented one instead of winging it, what a pain.

 

[swathdiver]

I dropped my trans pan and filter with a new gasket in my 2014 Tahoe Saturday. Luckily my flange exhaust bolts weren't rusted at all and I did it by the book by dropping the exhaust.
So I couldn't find my torque wrench and I tried to wing it, and broke a bolt. Trust me, it didn't take much.
I'm not leaking fluid but I'm wondering if anyone has had experience drilling out a pan bolt? Should I get all new bolts cause I might have stretched the other bolts too much?
I'm concerned now that if I try to remove the other bolts the heads my break off, too.
Should have just gone and rented one instead of winging it, what a pain.

They get torqued to 80 inch pounds which is like 6-2/3rds foot pounds, just hand tight really. If it's not leaking you could just leave it.

If you are a nut about these things like I am, drill it out with progressively larger bits or use an Easy-Out kit. If you bugger the threads, you can use a heli-coil to replace them so a factory bolt can be used in that spot still.

 

[Joseph Garcia]

Should not be a problem to drill out, but use a centering drill bit for your first drill hole, or carefully use a punch to create a 'starter' indent in the broken bolt as close to the center of the bolt as possible. This will minimize the chances of damaging the threads, as you use progressively larger drill bits. If you have a full set of drill bits, be sure to use incrementally larger drill bits one at a time, stepping up diameters in your drill bit set.

 

[Fless]

As @Joseph Garcia noted, be sure to center your first hole. Pick up a lefthand drill bit set and drill in reverse, using progressively larger bits. The broken bolt may come out while drilling.

 

[Joseph Garcia]

As @Joseph Garcia noted, be sure to center your first hole. Pick up a lefthand drill bit set and drill in reverse, using progressively larger bits. The broken bolt may come out while drilling.

Most of my broken bolts came out on their own, as I progressed to larger drill bits.

 

[JonnyTahoe]

Replaced my Trans Filter about a month ago. Got lucky was able to get the pan off with the exhaust in place but did remove the heat shield. Never used a torque wrench just tightened till the bolts felt tight. Used the black gasket the filter came with also had a Felpro gasket on hand just in case. If I broke off a bolt I would certainly try to fix it.

 

[OR VietVet]

Don't think you need al new bolts. If pan is back off, I would try a very small punch with a point or a very small chisel bit and see if you can use a small tick hammer and coax the bolt body in a loosening pattern and when get enough showing can latch on to it and turn it out. Those small bolts have never had a problem of getting corroded at the threads in the aluminum casing and been hard to spin in the threads. If this does not work, then the centered hole punch and drill out with left handed drill bit should work because, again, I doubt the broken bolt is seized with corrosion.

 

[Brian1133]

Thanks for the advice. So I drilled thru the bolt in the center but could not get the extractor to work. But since it's not leaking I'll leave it for now and tackle it when I do the next change. I'll back out the bolts tomorrow and torque.
Thanks again to everyone.
Brian