Stuck transmission drain bolt. Looking for suggestions...

[AshleyQuick]

This 10mm hex bolt is on a 1995 Lexus so I'd imagine it's been there for many years. I've sprayed it with penetrating fluid and I'm wondering what else to try. More time for the fluid to work? It's only been an hour? And what after that if that doesn't seem to work?

Obviously, the last thing I want to do is round it out.

 

[Kira]

Give any penetrant a couple of days to work.
Try heating the bolt, let it cool to ambient. Do this twice or thrice.
Try heating the pan while shielding the bolt. Then, with a perfectly fitting wrench, give it a try.

Do whatever you do with heat to effect whatever the strong thread-lock requires.
Some joker may have sealed you up well.

 

[Silver]

Above, plus ping the bolt nice and hard with a punch. Don't bend the pan, just shock that bolt a few times.

 

[dlundblad]

I’d spray daily for at least a week with pb blaster. Assuming the head isn’t rounded, id try an impact at its lowest setting first.

 

[GON]

Do whatever you do with heat to effect whatever the strong thread-lock requires.
Some joker may have sealed you up well.

This. If there is thread locker on the bolt, you have to identify the steps to negate the thread locker. Typically heat. If the issue is thread locker, the problem may be easier to address than one thinks. Maybe even driving until the trans hits operating temperature, get the Lexus on jack stands, hit the bolt area with some supplemental heat.... and all MAY be well.

 

[atikovi]

Why don't you just drop the transmission pan and leave the bolt alone. Someone sealed it for a reason.

 

[Leo99]

How much experience do you have with removing stuck drain bolts and how much torque are you hitting the drain bolt with? I don't have much experience but I was determined to remove the differential drain on my old Rav4. I used my impact wrench after hammering in the hex socket. No way it was coming loose with a 3/8" ratchet or 18" breaker bar. It took a lot of persuading to loosen it. A lot more than would have guessed. I lack the experience to know how much torque is too much and your pan will be damaged.

 

[Brian123]

This 10mm hex bolt is on a 1995 Lexus so I'd imagine it's been there for many years. I've sprayed it with penetrating fluid and I'm wondering what else to try. More time for the fluid to work? It's only been an hour? And what after that if that doesn't seem to work?

Obviously, the last thing I want to do is round it out.

Do you have anyway to send us a pic?
You are using a 10mm hex bolt socket, if you are, then you need a breaker bar?

 

[IndyIan]

How much experience do you have with removing stuck drain bolts and how much torque are you hitting the drain bolt with? I don't have much experience but I was determined to remove the differential drain on my old Rav4. I used my impact wrench after hammering in the hex socket. No way it was coming loose with a 3/8" ratchet or 18" breaker bar. It took a lot of persuading to loosen it. A lot more than would have guessed. I lack the experience to know how much torque is too much and your pan will be damaged.

I had to go forward and back on the impact gun a few times to do the trans drain bolt on our 2006 CRV, it was in an aluminum pan, and let loose with a nice "crack!"... A few taps with a hammer and punch will help too, but an aluminum pan is a bit scary to beat on too much...

 

[JeffKeryk]

Make sure the drain plug hex is clean so the hex tool fits properly. It is of good quality; I would smack what ever tool you are using with a hammer to shock it.
Good luck.

 

[RooflessVW]

Put some valve lapping compound on your hex key for better grip.

Give it a sharp rap with a hammer instead of just pushing hard.

 

[tnt_motorsports]

I’d use a 6 point socket for sure. No box end wrench. Put a breaker bar on it and give it a couple swift blows with a hammer. If you have a small impact I’d consider that. I’m guessing aluminum pan and steel bolt has caused this issue for you.

Just my $0.02