Seized Transmission Oil Plugs

[John Nugent]

I have a slight problem, I was trying to change the gear oil in my tranny, with the use of a 17mm allen wrench to loosen the oil fill plug. I noticed that it was really tight! I struggled w/ it for a while and slipped twice, realizing that this wasn't going to work, I stopped. Does anyone have suggestions on a stuck/seized tranny plug?

[John Rogers]

I think Snap-on makes a removal tool for this as the size is used by a lot of other cars and it uses a breaker bar so you can put some force on it. I had the same problem and used a grade-8 bolt to fit the indentation and welded nuts(4) the length of the threads. Then welded an old 22 mm box end wrench to this and it works great. Looking back, it would have been easier to get the Snap-on tool but it was Sunday.

[Keith V]

John - I had a similar problem when I changed my gear oil a couple months ago. The car was up only as far as a couple jack stands, so there was little room to use the allen wrench on very tight plugs. So I cut a twelve inch piece of plumbing pipe to slip onto the end of the allen wrench. Even though I had to turn the plug a little, take out and replace the wrench, and turn again many times, the pipe gave me the extra leverage, and was an inexpensive fix. Also, being careful not to overtighten the plugs when I put them back in, I had a couple drops for a day or so until I tightened them just enough. I hope this helps. Regards, Keith V.

[Dave at Pelican Parts]

Before you try the "bigger hammer" approach, I would suggest hosing it down with Liquid Wrench, then using a hammer to THUMP on it a bit. Come back the next day, and do the same thing. And the next. Thumping with a hammer can sometimes help to break the friction between the fastener and the case. The wait can also help the penetrating oil to get into the threads.

I would normally suggest heating the case if that doesn't work, but I'm not sure that an open flame and a magnesium-alloy tranny case would mix very well. =8^O

If you find that you just cannot get the plugs out at ALL, I'd suggest taking it to a machine shop. Hopefully one experienced with Bug and/or Porsche motors, since some of those are made out of the same sort of magnesium alloy that the tranny case is.

Oh, and this is the reason that you ALWAYS remove the fill plug before you remove the drain plug. If the drain one is frozen, you can still drive the car. If the fill one is, ditto. Open up the drain plug first, and if the fill plug is the frozen one, you have to get the car towed--with the rear wheels OFF the ground!

--DD

[John Rogers]

I forgot about the heat and I had to get things hot on ours. I drove for a while and then raised it quickly when I got home and put a couple of ice cubes on the plug and held them on. I had used some liquid wrench, but there seemed to be none on the threads when I finally got it off. I used hi temp anti-seize when I put them back in.

[John Nugent]

Thanks everybody for your help. I got the plugs out and the transmission oil is changed. With Dave's advice, I cleaned the area w/ parts cleaner, sprayed the plug w/ some Liquid Wrench, then tapped it lightly w/ a hammer. I did this for a whole week before and after work.. Finally bought a plug socked, then it slowly loosen the plug out. Thanks again guys..