ZF Drain Plug Stuck
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Pro
Joined: Aug 2003
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From: South Boardman MI
ZF Drain Plug Stuck
I've been wanting to change out the tranny oil in my ZF6 but it is stuck but good. I can see the yellowish thread compound on it. I've been cranking on it pretty good and the opening is starting to deform. I don't want to strip it all the way.
Can I apply heat to the casing to get it off or is this dangerous for the material it's made from? (some of the older threads for this suggested it) What other suggestions do you all have?
Can I apply heat to the casing to get it off or is this dangerous for the material it's made from? (some of the older threads for this suggested it) What other suggestions do you all have?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Re: ZF Drain Plug Stuck (PreferEuroRacing)
that's aluminum... be careful!!!
I had to fight mine, too... 17mm 1/2 drive socket, with a big **** breaker bar...
Also, try some PB Blaster in the threads...
I had to fight mine, too... 17mm 1/2 drive socket, with a big **** breaker bar...
Also, try some PB Blaster in the threads...
Instructor
Joined: Jan 2004
Posts: 178
Likes: 3
From: Evansville IN
Re: ZF Drain Plug Stuck (PreferEuroRacing)
Before you get the drain plug loose, make sure you can get the fill plug out first. You don't want to drain it if you can't refill it.. You amy want to try jolting the wrench to see if you can shock the bolt loose after soaking it with wd40 or equivilant. Good luck
Race Director
Joined: Mar 1999
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From: Stafford, Virginia Kittah, Kittah, Kittah...
Re: ZF Drain Plug Stuck (richdwyer)
Before you get the drain plug loose, make sure you can get the fill plug out first. You don't want to drain it if you can't refill it.. You amy want to try jolting the wrench to see if you can shock the bolt loose after soaking it with wd40 or equivilant. Good luck
Very good advice!!!
My drain plug was very difficult so I worried about getting the fill plug off also... After I got the fill plug loosened I fought the drain plug out for the, "just incase" mentioned above...
To loosen mine up, I ended taking a hammer to the allen wrench... I few nice firm taps jarred it enough to loosen and remove...
Safety Car
Joined: Feb 2000
Posts: 4,564
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From: Austin Texas
Re: ZF Drain Plug Stuck (PreferEuroRacing)
You might try an air impact-wrench as well.
Mine was badly deformed from bottoming out on curbs (I do go "ag-racing" at times) and speed bumps, and I had to tack-weld the plug. So as not to destroy the tool, I found a bolt that the head would fit into the plug. Tack-welded it on 3 sides and then used a pipe-wrench to remove.
Since then I've used a small amount of anti-seize to the threads and actually torqued the plug to specs (not something I had done previously) and have had no issues. Got new plugs from ZFDoc to replace the fu$@ed up one and have a few spares in the tool-box.
If you use an impact the first time you try it, they come out with no problems. You start to run into deforming when trying to use a breaker-bar and holding the thing in place.
Mine was badly deformed from bottoming out on curbs (I do go "ag-racing" at times) and speed bumps, and I had to tack-weld the plug. So as not to destroy the tool, I found a bolt that the head would fit into the plug. Tack-welded it on 3 sides and then used a pipe-wrench to remove.
Since then I've used a small amount of anti-seize to the threads and actually torqued the plug to specs (not something I had done previously) and have had no issues. Got new plugs from ZFDoc to replace the fu$@ed up one and have a few spares in the tool-box.
If you use an impact the first time you try it, they come out with no problems. You start to run into deforming when trying to use a breaker-bar and holding the thing in place.
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Re: ZF Drain Plug Stuck (Joe90)
You might try an air impact-wrench as well.
Mine was badly deformed from bottoming out on curbs (I do go "ag-racing" at times) and speed bumps, and I had to tack-weld the plug. So as not to destroy the tool, I found a bolt that the head would fit into the plug. Tack-welded it on 3 sides and then used a pipe-wrench to remove.
Since then I've used a small amount of anti-seize to the threads and actually torqued the plug to specs (not something I had done previously) and have had no issues. Got new plugs from ZFDoc to replace the fu$@ed up one and have a few spares in the tool-box.
If you use an impact the first time you try it, they come out with no problems. You start to run into deforming when trying to use a breaker-bar and holding the thing in place.
Mine was badly deformed from bottoming out on curbs (I do go "ag-racing" at times) and speed bumps, and I had to tack-weld the plug. So as not to destroy the tool, I found a bolt that the head would fit into the plug. Tack-welded it on 3 sides and then used a pipe-wrench to remove.
Since then I've used a small amount of anti-seize to the threads and actually torqued the plug to specs (not something I had done previously) and have had no issues. Got new plugs from ZFDoc to replace the fu$@ed up one and have a few spares in the tool-box.
If you use an impact the first time you try it, they come out with no problems. You start to run into deforming when trying to use a breaker-bar and holding the thing in place.
Mine was also VERY tight and I had to make a tool using an old socket and a bolt with a 17mm head.
That is why I posted the question yesterday on this forum about using the drain plug that MAM is advertising for the C5; it has what appears to be a 3/8" square drive rather than a 17mm hex on it, and it is magnetic.
PS I took mine out cold, perhaps a hot gearbox would have made it easier?
Larry
Racer
Joined: Jul 2002
Posts: 401
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From: Aptos CA
Re: ZF Drain Plug Stuck (code5coupe)
I hate these plugs. This is the kind of thing that makes me crazy: Why torque a plug so tight you can't get it out and why use a plug that any "regular" tool can't get out without wrecking the plug? I wish manufacturing engineers had to repair their own parts before they make us crazy with them.
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Thread Starter
Pro
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From: South Boardman MI
Re: ZF Drain Plug Stuck (Skippy Stone)
Good discussion on this issue. I appreciate everyone's input. The fill plug I got off with minimum effort. I figured if worse came to worse I could drain with a pump and refill as normal. I was hoping to get the drain plug off, however, to make sure any metal bits at the bottom of the tranny came out with the oil.
At this point I am going to drive it until hot and see if I can get it to move after soaking it good with Blaster. That sounds like a good product to have around anyways. If that still doesn't work, I'll go the pump way.
Thanks, everyone.
At this point I am going to drive it until hot and see if I can get it to move after soaking it good with Blaster. That sounds like a good product to have around anyways. If that still doesn't work, I'll go the pump way.
Thanks, everyone.
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Re: ZF Drain Plug Stuck (PreferEuroRacing)
My drain plug was rubbed off pretty good from a meeting with a very high manhole cover one time...so bad in fact I could only get a bite on it with a pipe wrench! I was lucky enough to get two threads worth of grab on it...had to special order a new one 10 days prior from GM...
Is there any tool made for this? or is it engineer time??
Is there any tool made for this? or is it engineer time??
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 109
From: Austin Texas
Re: ZF Drain Plug Stuck (code5coupe)
Mine was/is steel. Same one that came from the factory (since I've owned the car since new).
A square-drive would sure be easier to get out, as long as it was the same thread size, etc. I don't see why you couldn't use one from the C5.
I think if I could find one with a square-drive or even a large torx (like a T55) it is better than the hex-head they have in there now.
A square-drive would sure be easier to get out, as long as it was the same thread size, etc. I don't see why you couldn't use one from the C5.
I think if I could find one with a square-drive or even a large torx (like a T55) it is better than the hex-head they have in there now.
Race Director
Joined: Dec 2002
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Joe90,
I wish mine were steel!! Yes, a square drive would be MUCH easier to remove than the shallow hex drive. As you said, even a Torx would be better.
Try putting a pipe wrench on the plug at the same time you use the 17mm tool. I know mine was a real BEAR to remove and I did deform the 17mm hex in the process.
Good luck.
Larry
I wish mine were steel!! Yes, a square drive would be MUCH easier to remove than the shallow hex drive. As you said, even a Torx would be better.
Try putting a pipe wrench on the plug at the same time you use the 17mm tool. I know mine was a real BEAR to remove and I did deform the 17mm hex in the process.
Good luck.
Larry
Last edited by rocco16; Jul 8, 2004 at 06:11 PM.
Melting Slicks
Joined: Apr 2003
Posts: 2,150
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From: NS
Originally Posted by PreferEuroRacing
I've been wanting to change out the tranny oil in my ZF6 but it is stuck but good. I can see the yellowish thread compound on it. I've been cranking on it pretty good and the opening is starting to deform. I don't want to strip it all the way.
Can I apply heat to the casing to get it off or is this dangerous for the material it's made from? (some of the older threads for this suggested it) What other suggestions do you all have?
Can I apply heat to the casing to get it off or is this dangerous for the material it's made from? (some of the older threads for this suggested it) What other suggestions do you all have?
When I re-installed it I used a little anti-seize and didn't torque as tight as factory specs. I think I stopped at 20 ft-lbs, plenty tight.
Race Director
Joined: Dec 1999
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You people must be using the wrong wrench, it's a 17mm allen wrench. Use that, don't use something that will fit approximately, use the correct wrench. I have used those big L shaped wrenches for a long time, tap the end with a hammer to break the seal and the plug comes out real easy. Also make sure it's fully seated so tap it a few times to make sure it's in all the way. There's no way you can round it off when you use the right tool and make sure it's inserted all the way.
Race Director
Joined: Dec 2002
Posts: 13,348
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by Twin_Turbo
There's no way you can round it off when you use the right tool and make sure it's inserted all the way.
Oh, yes. You can round it OUT while using the proper tool. You must also use the proper technique because some of the plugs are aluminum (soft) and the hex is very shallow.
Atok...I also torqued mine to only 20ft/lbs....I looked under the car yesterday only to see a drip of oil hanging on the plug and a quarter-sized spot on the drive!!!! Guess I'll put it up on ramps this morning and torque it to the proper specs.....
Larry
code5coupe
