82 Differential Plug
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Melting Slicks
Joined: Apr 2023
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From: Poplar Bluff MO
82 Differential Plug
I'm attempting to change the oil in my differential and the plug is not budging with a 3/8" breaker bar. The plug is the kind that has a 5/16" hex. Going to spray some break free on it. Just wondering if it's safe to use my air impact on low to try and break it free?
JT
JT
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Melting Slicks
Joined: Apr 2023
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From: Poplar Bluff MO
JT
Safety Car
Joined: Dec 2012
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From: Summerville SC
Try a 1/2" bar. Or a lot of times when I have had trouble breaking a bolt loose, I try to tighten it first. I can't tell you how or why that works, but it has worked for me many times. Maybe it just breaks the rust loose.
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Melting Slicks
Joined: Apr 2023
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From: Poplar Bluff MO
I can't tell from the couple of photos I found of 80-82 differential plugs if it's a tapered thread or an O-ring seal. Anyone know what kind of plug the 80-82 has?
JT
JT
Thread Starter
Melting Slicks
Joined: Apr 2023
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From: Poplar Bluff MO
I can answer both questions now, the plug has tapered threads and the impact just feathering the trigger to keep it low backed it out just fine.
Do you use any kind of sealer on the threads?
JT
Do you use any kind of sealer on the threads?
JT
Le Mans Master
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Melting Slicks
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From: Poplar Bluff MO
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Drifting
Joined: Jun 2025
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Yes I do on plug's threads, Either some common hardware aisle pipe dope OR Teflon tape.
Neither should be absolutely necessary. However, it might weep without it. Yes, belt & suspenders.
Melting Slicks
Joined: Apr 2021
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From: Minnesota
A sealant will help yes, but if you don’t want to use that a small dab of grease or other lubricant on the threads will allow you to get more torque on it, and make it easier to take it out in the future.
Drifting
Joined: Jun 2025
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Neither pipe dope or Teflon tape will hinder removing plug; not now nor ten years hence. The right tool for the job. And Both offer excellent lubricity.
Melting Slicks
Joined: Dec 2009
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From: Thunder Bay
Yes. Teflon pipe sealant. And don't overtorque it when you reinstall it. Just good and snug.
