Differential Plug Stuck, Stripped

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Looking at the 'hole' on the fill plug, I can't make out any flat surfaces so I'm not sure that any hex bit, even a larger one that you hammer in, has anything to grab. I think an extractor or replacing the entire cover is the route to go.
 
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funny how Subaru changed to the Torx on the rear on that 2015 Foz - my 12 Foz and 14 Crosstrek had the square (1/2') plugs. My newest Subaru, a MT base 2016 Impreza also has the square plugs. I generally change the diffs/manual trans every other year, (40-50k/yr). When you do get it sorted, as others have mentioned, anti-seize is a definite.
Mike B
 
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I tried about 5 times over a 2 year period to get the fill plug out of my old Rav4. It wouldn't budge. Breaker bars wouldn't move it. Finally got really mad at it. Hammered in a hex head socket good and deep. Put in an adapter, wore safety glasses and used my impact on it. Took some convincing but it eventually broke free.
 
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Is that diff housing aluminum or iron? If it is aluminum I am afraid of possibly broken bolts on the diff.
For that reason I am a little afraid to suggest the obvious of replacing the cover, if the bolts break things are going downhill fast.
 
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Is that diff housing aluminum or iron? If it is aluminum I am afraid of possibly broken bolts on the diff.
For that reason I am a little afraid to suggest the obvious of replacing the cover, if the bolts break things are going downhill fast.
In the video, it looks AL.

I think the best thing, might be for him to take it to a shop. A the first sign of trouble, stop digging , unless you have the tools on hand to keep going. If the OP does not have a mig welder, splined extractors, a torch, grinders, chisels, etc, it might be better to just stop and go to a shop, before the hole gets too deep.
 
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In the video, it looks AL.

I think the best thing, might be for him to take it to a shop. A the first sign of trouble, stop digging , unless you have the tools on hand to keep going. If the OP does not have a mig welder, splined extractors, a torch, grinders, chisels, etc, it might be better to just stop and go to a shop, before the hole gets too deep.
My thoughts exactly. It wont take much damage to put that car on a flat bed.
 
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Leave it alone, it's not broke.. There's only 85k miles accrued and no leaks mentioned. I know many more people who never touched their diff's than those who changed gear oil, not a single one ever had a problem with their differential for the remaining life of the care or truck with the original gear oil.
 

Chuck61

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My thoughts exactly. It wont take much damage to put that car on a flat bed.
Well, I haven’t done anything else yet. I haven’t even had time to swing by the shop and see if they could break it free for me. I’m just curious though, what kind of damage are we talking? Couldn’t I just replace any broken bolts? (I really don’t know)
 
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Well, I haven’t done anything else yet. I haven’t even had time to swing by the shop and see if they could break it free for me. I’m just curious though, what kind of damage are we talking? Couldn’t I just replace any broken bolts? (I really don’t know)
You could end up with bolts broken in the diff housing. I can't tell from the video if the are open bolt holes or closed on the back side. If open you can have a lot of corrosion around the distal end of the bolt. If you can't get the broken bolts out of the housing you will end up on the flat bed as there is no oil in the diff, can't just tow it.
Pound too hard seating a larger hex or even a splined extractor and crack the cover.
The fastest easiest option as Trav mentioned , is to mig weld a bolt in the hex bolt. Gives you a head to turn and the heat from the mig usually loosens the corrosion or thread locker.
 

JC1

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Well, I haven’t done anything else yet. I haven’t even had time to swing by the shop and see if they could break it free for me. I’m just curious though, what kind of damage are we talking? Couldn’t I just replace any broken bolts? (I really don’t know)
I think what Trav and others are saying is that if the diff cover bolts break off then you have to get those out and it's a bigger mess. You are already having issues accessing the drain plug and without welder etc, you may get into larger problems.

What are you comfortable with? Maybe it's best to get the new cover and drain bolts and get a shop to remove the old stuff and install the new and make sure they put antisieze etc on the new ones and don't over torque anything.
 
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In the video, it looks AL.

I think the best thing, might be for him to take it to a shop. A the first sign of trouble, stop digging , unless you have the tools on hand to keep going. If the OP does not have a mig welder, splined extractors, a torch, grinders, chisels, etc, it might be better to just stop and go to a shop, before the hole gets too deep.

Or, get a new diff cover/gasket, 30 mins replacement....lol
 

Chuck61

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Well, I haven’t done anything else yet. I haven’t even had time to swing by the shop and see if they could break it free for me. I’m just curious though, what kind of damage are we talking? Couldn’t I just replace any broken bolts? (I really don’t know)
Ah, I see what you mean. If the bolt breaks off in the Diff housing it’s a high pita
 
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#1 Clean dirt out of socket.
#2 Use ball end of ball peen hammer on socket dead on a few times. The object is to move the stripped out metal back into the hole
#3 try 10mm allen, if it doesn't fit see step #4, if it does fit return to step #3
#4 carefully drive allen into the socket with hammer
#5 give handle of allen a sharp rap side wise with hammer to loosen plug
This process has 100% success rate on every "stripped" socket head I've ever encountered
 
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