Best tool for rounded hex bolt head

TRevs

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I rounded the shoulders on a caliper bleeder bolt last week; the 3/8 wouldn’t quite fit and the 10mm was slightly loose. When it didn’t come loose easily I sprayed Liquid Wrench a few times over a couple hours, and to avoid snapping it off I used the 18v impact. I thought it was turning the bolt but realized too late that it just rounded the head.

Is there a good tool for removing? Maybe just pound a 12-pt socket on? I really don’t want to have to drill it out or replace the caliper. (This is a Ford Super Duty van.)
 
I rounded the shoulders on a caliper bleeder bolt last week; the 3/8 wouldn’t quite fit and the 10mm was slightly loose. When it didn’t come loose easily I sprayed Liquid Wrench a few times over a couple hours, and to avoid snapping it off I used the 18v impact. I thought it was turning the bolt but realized too late that it just rounded the head.

Is there a good tool for removing? Maybe just pound a 12-pt socket on? I really don’t want to have to drill it out or replace the caliper. (This is a Ford Super Duty van.)

It’s toast. Cannot be fixed. The rIg is currently not safe to drive. You will need to replace the entire axle with a ‘60.

(At least, that’s how I would explain it to the wife…😉)
 
This is just an example, but I’ve always had good results with this type on a severely rounded off bolt/nut as long s you have to room to fit it on the hardware. I have and old Craftsman set.
https://www.amazon.com/dp/B087P5GKFK?tag=wranglerorg-20

IMG_0832.jpeg
 
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Sold by: Luckyway- perfectly named for this chinesium product.

Maybe you pound on a 9mm if the 10 is too big. Dont forget a little propane torch heat might help here too with your spray lube.
 
I have never had a bleeder get stuck before. I figured the impact on medium was safer than a large ratchet/breaker bar. I should have done the alternating tighten/loosen method…. Or maybe tried harder to get the 3/8” socket to fit. For some reason the rear caliper bleeders were just a bit over 3/8 but the 3/8 socket went right on the front calipers. Well, it was two days before a 900-mile road trip and I really didn’t want it to break. I bled the rest of the system so the fluid is 90% clean now.

I think the vice grips/liquid wrench/ propane heat will be the next step.
 
I have never had a bleeder get stuck before. I figured the impact on medium was safer than a large ratchet/breaker bar. I should have done the alternating tighten/loosen method…. Or maybe tried harder to get the 3/8” socket to fit. For some reason the rear caliper bleeders were just a bit over 3/8 but the 3/8 socket went right on the front calipers. Well, it was two days before a 900-mile road trip and I really didn’t want it to break. I bled the rest of the system so the fluid is 90% clean now.

I think the vice grips/liquid wrench/ propane heat will be the next step.

Put some Russell Speed Bleeders on that Superduty, at least on the rears. The fronts will gravity bleed easy but the rears will take till next Christmas.
 
I found the long nose guys fit nicely in there.

View attachment 584734

That's the same tool I've used for that situation several times - always successfully. I'm actually in the habit of putting a six-point, deep socket on bleeders to break them free before bleeding - to avoid rounding the corners. It almost always works, even when I lived in the Rust Belt.